Patent Document

FIELD OF THE INVENTION  
       [0001]     The present invention relates to a process by which a material can be placed onto a moving web and more particularly to a process by which a material can be placed onto a moving web across at least a portion of the transverse width of the web.  
       BACKGROUND OF THE INVENTION  
       [0002]     There are many processes which allow for the application of material across the transverse width of a web. However, many of these processes accomplish this feat at the cost of affecting the speed of the entire web.  
         [0003]     An example of modifying the speed of only a portion of the web as opposed to modifying the speed of the entire web is shown in U.S. Pat. No. 5,693,165 issued to Schmitz. The Schmitz reference teaches that a pair of translatable transport rollers may be used in conjunction with a pair of stationary guide rollers to affect a velocity change in a portion of the web. The transport rollers are mounted on a sled which is periodically translated along a frame. Because the web is looped around the translatable transport rollers, as the sled translates along the frame in the direction of web feed, the web portion between the two translatable transport rollers has a velocity which is less than that of the overall web velocity. Therefore, a process could be implemented wherein a material is placed onto the portion of the web having a reduced velocity.  
         [0004]     European Patent Application EP-A-0 364 087 discloses an applicator device for applying layers of material generally transversely across an elongated web. The elongated web moves continuously through the device in a web feed direction at a predetermined web speed. The device comprises two transport members which each turn the web 90 degrees in the plane of the web. The web portion between the two transport members is of constant length and extends perpendicular to the upstream portion of the web. The transport members are mounted on a sled which translates in the web feed direction and the reverse web feed direction. When the sled translates in the web feed direction at a speed which equals the web speed, the web portion between the transport members is stationary relative to the frame. A rotating applicator wheel having a tangential speed, which equals the linear speed of the air bars, can contact the web portion to attach a layer of material. When the frame is translated in the reverse web feed direction, the web portion is accelerated past the transport members to the web&#39;s downstream side.  
         [0005]     From European Patent application EP-A-0 284 652 it is known to supply tensioned elastic ribbons transversely to a continuously moving web at a high speed. A number of applicator heads are mounted on a rotatable vertical shaft with each applicator head being connected to a radial arm. Upon rotation of the shaft, the arms pass over the moving web. At the position when a radial arm extends perpendicular to the web and has a tangential velocity equal to the linear web speed, a pre-stretched elastic is fed from the applicator head. A rotating anvil, which has a circumferential velocity equal to the linear web speed to minimize the shearing forces, contacts the applicator head upon attachment of the elastic.  
         [0006]     Because the above apparatus has multiple arms, it can attach transverse parts to the moving web at a high speed and exert a low tension on the web with the web speed remaining constant. But, the application of complex parts in a transverse orientation to the web may require momentarily stopping the web at the position of the applicator device. In this instance, the above apparatus is less suitable.  
         [0007]     It is an object of the present invention to provide a method by which a material may be applied to a moving web transversely without affecting the overall processing speed of the web regardless of the complexity of the material to be applied to the web.  
       SUMMARY OF THE INVENTION  
       [0008]     The present invention pertains to a method of placing a material on a plurality of webs. The method comprises the steps of providing a first path comprising a first upstream zone, a first downstream zone, and a first intermediate zone which is disposed between the first upstream zone and the first downstream zone. Also, a second path is provided comprising a second upstream zone, a second downstream zone, and a second intermediate zone which is disposed between the second upstream zone and the second downstream zone. In addition, the first intermediate zone comprises a first assembly, and the second intermediate zone comprises a second assembly.  
         [0009]     A first web having a transverse width and a longitudinal centerline is provided in the first upstream zone of the first path such that the first web is moving at a first web velocity in the positive x direction. The first assembly is provided for diverting the first web from the first upstream zone to the first intermediate zone of the first path. The first assembly also diverts the first web from the first intermediate zone to the first downstream zone of the first path.  
         [0010]     Similarly, a second web having a transverse width and a longitudinal centerline is provided in the second upstream zone of the second path such that the second web is moving at a second web velocity in the positive x direction. The second assembly is provided for diverting the second web from the second upstream zone to the second intermediate zone of the second path and for diverting the second web from the second intermediate zone to the second downstream zone of the second path.  
         [0011]     The method further comprises the step of periodically overlapping the first and second assemblies in an alternating fashion. This is accomplished by translating the first assembly and the second assembly in a positive x direction in a first plane and a negative x direction in a second plane. So, when the first assembly translates in the positive x direction, the first web in the first intermediate zone has a velocity, with respect to the first assembly, which is less than the first web velocity. Similarly, when the second assembly translates in the positive x direction, the second web in the second intermediate zone has a velocity, with respect to the second assembly, which is less than the second web velocity.  
         [0012]     As the first and second assemblies are being overlapped, a material is being alternately applied across at least a portion of the transverse width of the first web in the first intermediate zone and across at least a portion of the transverse width of the second web in the second intermediate zone. As a result of the alternate application of the material to the first web and the second web, the application of the material is continuous.  
         [0013]     Alternatively, the claimed invention may be performed on a single web rather than the previously stated plurality of webs. In this instance, the method includes the step of providing a single web to a first upstream zone such that the single web is moving at a first upstream zone velocity. Also, a first assembly is provided for diverting the single web from a first upstream zone to a first intermediate zone. The first assembly also diverts the single web in the first intermediate zone to a first downstream zone. From the first downstream zone, the single web is transported into a second upstream zone such that the single web is moving at a second upstream zone velocity in the positive x direction. In addition, a second assembly is provided for diverting the single web from the second upstream zone to a second intermediate zone. The second assembly also diverts the single web from the second intermediate zone to a second downstream zone.  
         [0014]     This method further comprises the step of periodically overlapping the first and second assemblies in an alternating fashion. This is accomplished by translating the first assembly and the second assembly in a positive x direction in a first plane and a negative x direction in a second plane. So, when the first assembly translates in the positive x direction, the single web in the first intermediate zone has a velocity, with respect to the first assembly, which is less than the first upstream zone velocity. Similarly, when the second assembly translates in the positive x direction, the single web in the second intermediate zone has a velocity, with respect to the second assembly, which is less than the second upstream zone velocity. As the assemblies periodically overlap in an alternating fashion, a material is continuously applied across at least a portion of the transverse width of the single web in the first intermediate zone and the transverse width of the single web in the second intermediate zone. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]      FIG. 1  is a plan view of an apparatus that can carry out the present invention.  
         [0016]      FIGS. 2-5  show a cross sectional view of the apparatus shown in  FIG. 1  illustrating an example of the motion of the two assemblies relative to one another.  
         [0017]      FIGS. 6-7  show a cross sectional view of the apparatus shown in  FIG. 1  illustrating an example of the assembly motion that can perform an optional step in the claimed invention.  
         [0018]      FIG. 8  is a view of a portion of web material showing the uniform application of material onto the portion of the web.  
         [0019]      FIG. 8A  is a graph of an example of the velocity profiles of the first and second assembly.  
         [0020]      FIG. 9  is a view of a portion of web material showing a variant of uniform application of the material onto the portion of the web.  
         [0021]      FIG. 10  is a view of a portion of web material showing the angled application of the material onto the portion of the web.  
         [0022]      FIG. 11  is a view of a portion of web material showing the angled application of the material onto the portion of the web.  
         [0023]      FIG. 12  is a cross sectional view of an apparatus implementing an optional step in the claimed invention.  
         [0024]      FIG. 13  is a plan view of an apparatus that implements an optional step in the claimed invention.  
         [0025]      FIG. 14  is a plan view of an apparatus that can carry out a variation of the claimed invention.  
         [0026]      FIG. 15  is an elevation view of an apparatus that can carry out a variation of the claimed invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0000]     Definitions:  
         [0027]     As used herein, the following terms have the following meanings:  
         [0028]     The term “continuous” when used to refer to a process, means that the process, when in operation, can run without stopping; however, the process can be stopped. When used to refer to a web, the term “continuous” means that the web subjected to the process is sufficiently long such that the first and second assemblies, later defined herein, can each perform at least two complete cycles.  
         [0029]     The term “web,” as used herein, implies a continuous web and may comprise non-wovens, wovens, films, tissues, laminate structures, or any combination thereof.  
         [0030]     The term “cycle” refers an interval of time characterized by the occurrence of a sequence of events. In this instance, the cycle for an assembly begins when its web receives a material on its leading edge. Subsequently, the web via its assembly moves in such a manner so that the web can receive the material again. The end of the cycle for the assembly occurs at a time immediately prior to the material contacting the web on its leading edge.  
         [0031]     As used herein the term “machine direction,” designated MD, is the direction parallel to the flow of the web through the equipment.  
         [0032]     As used herein the term “cross machine direction,” designated CD, is the direction that is substantially perpendicular to the machine direction.  
         [0033]     As used herein the term “transverse width” is the width of the web in the CD direction.  
         [0034]     As used herein, the x-axis is parallel to the longitudinal centerline of the web(s) of the first and second upstream and downstream zones.  
         [0035]     As used herein, the y-axis is perpendicular to the x-axis and the longitudinal centerline of the web(s) of the first and second upstream and downstream zones.  
         [0036]     As used herein, the z-axis is perpendicular to the x-axis, the y-axis, and the top surface of the web.  
         [0000]     Description  
         [0037]      FIG. 1  shows an example of an apparatus  10  that can carry out the present invention. A first web  12  is provided in a first upstream zone  92  moving in the positive x direction  93  at a first web velocity. A first assembly  28  is provided to divert the first web  12  from the first upstream zone  92  to a first intermediate zone  90 . The first web  12  is diverted by a first turnbar  14  such that the first web extends in the positive y direction toward a second assembly  30 . The first web  12  is turned, such that the longitudinal centerline  302  of the first web  12  in the first intermediate zone  90  is perpendicular to the longitudinal centerline  300  of the first web  12  in the first upstream zone  92 .  
         [0038]     The first web  12  is fed to a first idler  18  such that the first web  12  in the first intermediate zone  90  is inverted. The first web  12  is inverted such that the first web  12  extends in the negative y direction away from the second assembly  30 . The first web  12  is then fed to a second turnbar  16  where the first web  12  is diverted from the first intermediate zone  90  to a first downstream zone  94 . The first web  12  is turned such that the longitudinal centerline  304  of the first web  12  in the first downstream zone  94  is parallel to the x-axis and moves in the positive x direction  95 .  
         [0039]     Similarly, a second web  20  is provided in a second upstream zone  98  moving in the positive x direction  99  at a second web velocity. The second assembly  30  is provided to divert the second web  20  from the second upstream zone  98  to a second intermediate zone  96 . The second web  20  is diverted by a third turnbar  22  such that the second web extends in the negative y direction toward the first assembly  28 . The second web  20  is turned, such that the longitudinal centerline  308  of the second web  20  in the second intermediate zone  96  is perpendicular to the longitudinal centerline  306  of the second web  20  in the second upstream zone  98 .  
         [0040]     The second web  20  is fed to a second idler  26  such that the second web  20  in the second intermediate zone  96  is inverted. The second web  20  is inverted such that the second web  20  extends in the positive y direction away from the first assembly  28 . The second web  20  is then fed to a fourth turnbar  24  where the second web  20  is diverted from the second intermediate zone  96  to a second downstream zone  100 . The second web  20  is turned such that the longitudinal centerline  310  of the second web  20  in the second downstream zone  100  is parallel to the x-axis and moves in the positive x direction  101 .  
         [0041]     As shown in  FIGS. 2-5 , a material applicator  32  is provided for placing a material  34  onto a first web  12  and a second web  20 . The material  34  can be a polymer as exampled by an adhesive or an elastomeric material. The material  34  can also be a thermoplastic or any non-woven fiber. Also, the material  34  may comprise a web from which discrete parts are formed, as discussed with regard to  FIG. 15 . Moreover, the material applicator  32  may apply the material  34  via an extrusion process, a spraying process or a joining process or any combination thereof.  
         [0042]     In  FIG. 2 , a distal end  38  of the material  34  is shown in contact with the leading edge  82  of the first web  12  which marks the beginning of the first assembly&#39;s cycle. The first web  12  in the first intermediate zone  90  continues to receive the material  34  as the first assembly translates in the positive x direction along a first plane  21 . Because the first assembly  28  translates in the positive x direction, the first web  12  in the first intermediate zone  90  has a velocity, with respect to the first assembly  28 , which is lower than the first web velocity. In contrast, the second assembly  30  translates in the negative x direction along a second plane  31  such that the second web  20  in the second intermediate zone  96  has a velocity, with respect to the second assembly  30 , which is greater than the second web velocity.  
         [0043]     As shown in  FIG. 3 , the distal end  38  of the material  34  is in contact with the trailing edge  84  of the first web  12 . After the material  34  has been applied across the transverse width of the first web  12  in the first intermediate zone  90 , the first assembly  28  moves along the z-axis in the negative z direction  23 . The second assembly  28  moves along the z-axis in the positive z direction  33  such that the second web  20  in the second intermediate zone  96  can receive the material  34  across its transverse width.  
         [0044]     As shown in  FIG. 4 , the distal end  38  of the material  34  is in contact with the leading edge  86  of the second web  20  in the second intermediate zone  96  which marks the beginning of the second assembly&#39;s cycle. The second web  20  in the second intermediate zone  96  continues to receive the material  34  as the second assembly  30  translates in the positive x direction along the first plane  21 . Because the second assembly  30  translates in the positive x direction, the second web  20  in the second intermediate zone  96  has a velocity, with respect to the second assembly  30 , which is lower than the second web velocity. Contemporaneously, the first assembly  28  translates in the negative x direction along the second plane  31  such that the first web  12  in the first intermediate zone  90  has a velocity, with respect to the first assembly  28 , which is greater than the first web velocity.  
         [0045]     As shown in  FIG. 5 , the distal end  38  of the material  34  is in contact with the trailing edge  88  of the second web  20 . After the material  34  has been applied across the transverse width of the second web  20  in the second intermediate zone  96 , the second assembly  30  moves in the negative z direction  37 . The first assembly  28  moves along the z-axis in the positive z direction  27  such that the first web  12  in the first intermediate zone  90  can receive the material  34  across its transverse width.  
         [0046]     The end of the cycle for the first assembly  28  corresponds to the moment immediately before the distal end  38  of the material  34  contacts the leading edge  82  of the first web  12 . Similarly, the end of the cycle for the second assembly  30  is the moment immediately before the distal end  38  of the material  34  contacts the leading edge  86  of the second web  20 .  
         [0047]     Although not shown in  FIG. 3 , when the distal end  38  of the material  34  contacts the trailing edge  84  of the first web  12 , the second assembly  30  is positioned immediately behind the first assembly  28  such that the risk of losing material between the first assembly  28  and the second assembly  30  is minimized. Similarly, although not shown in  FIG. 5 , when the distal end  38  of the material  34  contact the trailing edge  88  of the second web  20 , the first assembly  28  is positioned immediately behind the second assembly  30 .  
         [0048]     In the preceding figures, i.e.  2 - 5 , the movement of both the first assembly  28  and the second assembly  30  were shown as orthogonal to either the x-axis or z-axis merely as examples of the movements of the assemblies. However, the assemblies are not constrained to move solely in directions which are orthogonal to an axis described herein. Moreover, the movements of the assemblies are not constrained to move solely in a linear fashion. For instance, the assembly movement may comprise a curvilinear path.  
         [0049]     A separating step may be included in the present invention (see  FIG. 6 ). A separator  62  may be employed such that the material  34  is separated from the trailing edge  84  of the first web  12 . When the distal end  38  of the material  34  contacts the trailing edge  84  of the first web  12 , the separator  62  moves along a path  61 . The separator  62  severs the distal end  38  of the material  34  from the trailing edge  84  of the first web  12 . The separator  62  then moves along a path  63  such that the separator  62  does not disturb the movement of the first assembly  28  or second assembly  30 . The separator  62  operates in a similar manner when severing the distal end  38  of the material  34  from the trailing edge  88  of the second web  20  (See  FIG. 7 ).  
         [0050]     Because there are so many possibilities with regard to either the material  34  or the process utilized by the material applicator  32  to apply the material  34 , the step of separation may be accomplished in many different ways. The separator  62  can be a knife-edge which severs the distal end  38  of the material  34  from the trailing edge  84  of the first web  12  or the trailing edge  88  of the second web  20 . Moreover, if the material  34  comprises discrete parts, the separator may comprise a knife roll and an anvil roll (see discussion of  FIG. 15 ). The separator  62  may also comprise a hot air knife, a hot wire, a water jet, a laser, or any means of separation that is well known in the art.  
         [0051]     Alternatively, the step of separation of the material  34  from the trailing edge  84  of the first web  12  or the trailing edge  88  of the second web  20  can be accomplished by changing the velocity profile of the first assembly  28  or the velocity profile of the second assembly  30 . For example, when the distal end  38  of the material  34  is in contact with the trailing edge  84  of the first web  12 , the first assembly  28  accelerates to a higher velocity in the positive x direction than the velocity of the first assembly  28  when the first web  12  is receiving the material  34 . This acceleration to a higher velocity induces the material  34  to break, thereby accomplishing the step of separation. Similarly, when the distal end  38  of the material  34  contacts the trailing edge  88  of the second web  20 , the separation of the material  34  from the trailing edge  88  of the second web  20  can be accomplished by accelerating the second assembly  30 .  
         [0052]     Alternatively, the step of separation may be accomplished via a timed process. For instance, if the material is an adhesive to be sprayed onto the first web  12 , the material applicator  32  ceases the process when the trailing edge  84  of the first web  12  is no longer underneath the material applicator  32 . In this instance, the material applicator  32  ceases spraying the adhesive in between the trailing edge  84  of the first web  12  and the leading edge  86  of the second web  20 , and the material applicator  32  begins spraying once the leading edge  86  of the second web  20  is underneath the material applicator  32 . Similarly, the material applicator  32  ceases spraying between the trailing edge  88  of the second web  20  and the leading edge  82  of the first web  12 .  
         [0053]      FIGS. 8, 9 ,  10 , and  11 , are examples of the orientation of the material  34  on either the first, second, or single web. In  FIG. 8 , the material  34  is shown applied in a uniform manner to the web material perpendicular to the y-axis. As an example of how to accomplish this, the first assembly translates in the positive x direction at the first web velocity such that the first web in the first intermediate zone is stationary with respect to the first assembly. Because the first web in the first intermediate zone is stationary with respect to the first assembly, the material is applied across the transverse width of the first web in the first intermediate zone such that the material is perpendicular to the longitudinal centerline of the first web.  
         [0054]      FIG. 8A  provides examples of the velocity profiles of the assemblies for accomplishing the material orientation as shown in  FIG. 8 . As shown, time, denoted as “t”, t equal to zero, the first web in the first intermediate zone begins to receive the material. While receiving the material, the velocity of the first assembly in the positive x direction, denoted v1, is equal to the first web velocity. At time t equal to t1 (t1 representing the completion of 50% of the cycle for the first assembly), the transverse width of the first web has received the material. The first assembly subsequently completes the remainder of its cycle and gets back into a position such that the first web may receive the material again. Because 50% of the first assembly&#39;s cycle is spent receiving material across the transverse width of the first web, during the remaining 50% of the cycle, the amount of web which travels through the first intermediate zone is equal to the transverse width of the first web. Therefore, the material applicator provides the material to the first web in the first intermediate zone on a portion of the first web having a length which is two times the transverse width of the first web.  
         [0055]     The velocity profile of the second assembly is similar to that of the first assembly; however, the second web in the second intermediate zone begins to receive the material at t equal to t2. Similarly, at t equal to t3 (t3 representing the completion of 50% of the cycle for the second assembly) the transverse width of the second web has received the material.  
         [0056]     In  FIG. 9 , the material  34  is shown applied to the web in the first intermediate zone of the first assembly in two separate material applications  175  and  177 . During the first application  175  of the material  34  to the first web, the velocity of the first assembly while translating in the positive x direction is equal to the first web velocity. The translation of the first assembly in the positive x direction at the first web velocity causes the first web in the first intermediate zone to be stationary with respect to the first assembly. The first web in the first intermediate zone receives the material  34  across its transverse width for 50% of the first assembly&#39;s cycle. The remaining 50% of the cycle, the first assembly alternates positions with the second assembly and moves such that the first web can receive the material  34  during the second application  177 . Similar to the first application  175 , during the second application  177  of material  34 , the first assembly translates in the positive x direction at a velocity which equals the first web speed.  
         [0057]     In this instance, however, the gap between the first application  175  and the second application  177  occurs because during the first application  175  the material applicator does not provide material  34  to a portion of the first web having a length which is two times the transverse width of the first web. Instead, the material applicator applies the material  34  to a length of the first web which is less than two times the transverse width of the first web. Thus, before the second application  177  of material  34  begins, a portion of the first web passes through the first intermediate zone without receiving the material  34 .  
         [0058]      FIG. 10 , shows the orientation of the material  34  on the web when the velocity of the first assembly in the positive x direction is less than the first web velocity. If this is in fact the case, then the first web in the first intermediate zone has a positive velocity with respect to the first assembly. Because the first web in the first intermediate zone has a positive velocity with respect to the first assembly, the first web translates in the positive y direction thereby yielding a pattern similar to that shown in  FIG. 10 .  
         [0059]      FIG. 11 , shows the orientation of the material  34  on the web when the velocity of the first assembly in the positive x direction is greater than the first web velocity. If this is in fact the case, then the first web in the first intermediate zone, with respect to the first assembly, has a negative velocity with respect to the assembly. This causes the first web in the first intermediate zone to travel in the negative y direction with respect to the first assembly.  
         [0060]     Note that in both  FIGS. 10 and 11 , reference was made only to the first web. The same holds true for the second web; however, a positive second web velocity with respect to the second assembly, i.e. the second assembly is translating at a higher velocity than the velocity of the second web, causes the second web in the second intermediate zone to translate in the positive y direction. Therefore, a pattern similar to that shown in  FIG. 10  would occur. In contrast, a negative second web velocity with respect to the second assembly (the second assembly translates at a lower velocity than the velocity of the second web) causes the second web in the second intermediate zone to translate in the negative y direction with respect to the assembly. Therefore, a pattern similar to that shown in  FIG. 11  occurs.  
         [0061]     Once the material  34  has been applied to the first web  12  or the second web, then a laminate structure  64  may be formed by joining the first web  12  or second web with a third web  70  or fourth web, respectively.  FIG. 12  shows an example of how the laminate structure can be formed. The first web  12  in the first downstream zone  94  proceeds into a nip roll at which point the first web  12  is combined with the third web  70 . The combination or nipping takes place between roll A  66  and roll B  68 . The combination of the first web  12  and the third web  70  produces a laminate structure  64  on the downstream side of the nipping step. Similarly, although not shown in this figure, the second web could be combined with a fourth web in a similar manner. The discussion pertaining to the addition of the joining step for a single web application occurs in the section pertaining to  FIG. 14 .  
         [0062]     The orientation of the web face prior to the joining step may be of concern. For example, if the material were an elastic, over which a third web  70  or fourth web were to be placed, then the web going over a turnbar needs to be positioned such that the elastic were facing upward on the downstream side of the turnbar.  
         [0063]     The first web  12  and second web  20  may be drawn from a single parent roll of material  40  which forms a parent web  48  and is cut via a slitter  42  as shown in  FIG. 13 . The slitter  42  may comprise any suitable device known in the art. For example, the slitter  42  can be a stationary blade or may comprise an anvil roll and a cutting roll. The anvil roll and cutting roll may be configured such that they create a scissor cut or create a crush cut in a parent web  48 .  
         [0064]     For this embodiment, the parent roll  40  unwinds and creates a parent web  48 . The parent web  48  moves in the positive x direction towards the slitter  42 . The slitter  42  cuts the parent web  48  and creates a first web  12  and a second web  20  from the parent web  48 . The first web  12  and the second web  20  are then turned in a direction parallel to the y-axis, i.e. the first web  12  extends in the negative y direction while the second web  20  extends in the positive y direction. Then, the first web  12  and the second web  20  are turned such that the first web  12  and the second web  20  travel along a path parallel to the x-axis by the fifth turnbar  44  and the sixth turnbar  46 , respectively. After going through the fifth turnbar  44 , the first web  12  is provided to the first upstream zone  92 . Similarly, after going through the sixth turnbar  46 , the second web  20  is provided to the second upstream zone  98 .  
         [0065]     Alternatively, the present invention may be performed on a single web  152  using the apparatus  110  an example of which is shown in  FIG. 14 . The single web  152  is fed from the unwind station  158  into the first upstream zone  192  at a first upstream zone velocity in the positive x direction  193 . The single web  152  is diverted from the first upstream zone  192  into the first intermediate zone  190  and into the first assembly  128  by the first turnbar  114 . The single web  152  is turned such that the single web  152  in the first intermediate zone  190  extends in the positive y direction parallel to the y-axis. The single web  152  is then inverted by the first idler  118  such that the single web  152  extends in the negative y direction. Then the single web  152  is diverted from the first intermediate zone  190  to the first downstream zone  194  by the second turnbar  116 . The single web  152  is turned such that the single web  152  in the first downstream zone  194  moves in the positive x direction  195 .  
         [0066]     The single web  152  is transported to the second upstream zone  198  via the seventh turnbar  154 , eighth turnbar  156 , and third idler  160 . The single web  152 , from the first downstream zone  194  is diverted by the seventh turnbar  154  such that the single web  152  moves in the positive y direction  197 . The single web  152  is fed to the eighth turnbar  156  thereby turning the single web  152  such that the single web  152  moves in the negative x direction  199 . The single web  152  is then inverted by the third idler  160  such that the single web  152  moves in the positive x direction  201  and into the second upstream zone  198  at a second upstream zone velocity.  
         [0067]     The single web  152  is diverted from the second upstream zone  198  into the second intermediate zone  196  and into the second assembly  130  by the third turnbar  124 . The single web  152  is turned such that the single web  152  in the second intermediate zone  196  extends in the negative y direction parallel to the y-axis. The single web  152  is then inverted by the second idler  126  such that the single web  152  extends in the positive y direction. Then the single web  152  is diverted from the second intermediate zone  196  to the second downstream zone  200  by the fourth turnbar  122 . The single web  152  is turned such that the single web  152  in the second downstream zone  200  moves in the positive x direction  203 .  
         [0068]     The first assembly  128  and the second assembly  130  are periodically overlapped in an alternating fashion. Similar to the previous discussion, this allows a material to be continuously applied to the single web  152  in the first intermediate zone  190  and the second intermediate zone  196 , respectively.  
         [0069]     Also, the single web  152  can be combined with a third web or fourth web in a similar manner as described above with regard to  FIG. 12 . The combining in this instance could take place in the first downstream zone  194  or the second downstream zone  200  of the single web  152 . Moreover, the step of separation may be accomplished in any manner described herein.  
         [0070]      FIG. 15  shows an example of how discrete parts may be applied transversely to a moving web using apparatus  210 . The separation occurs using an anvil roll  204  and a knife roll  202 . The knife roll  202  has protrusions which engage the anvil roll  204  to create the discrete parts  206 . Material  234  comprises a web and is partially looped around the anvil roll  204 . As the protrustions of the knife roll  202  engage the anvil roll  204 , discrete parts  206  are formed from the material  234 . The anvil roll  204  engages the second web  220  in the second intermediate zone  296  in order to join the discrete part  206  to the second web  220  in the second intermediate zone  296 . Thus, the discrete parts  206  are combined with the second web  220  in the second intermediate zone  296  as the second web  220  passes underneath the anvil roll  204 .  
         [0071]     After the second web  220  in the second intermediate zone  296  has received the discrete part, the second assembly  230  translates in the positive x direction such that the first assembly  228  can move into a position such that the first web  212  in the first intermediate zone  290  can receive the discrete part from the anvil roll  204 . The anvil roll  204  has a tangential velocity which is equal to the velocity of the first assembly  228  when in contact with the first assembly  228 . Similarly, the anvil roll  204  has a tangential velocity which is equal to the velocity of the second assembly  230  when in contact with the second assembly  230 .  
         [0072]     The motions of the first assembly  28  and the second assembly  30  discussed previously concerning  FIGS. 2-5  are equally applicable in this instance regarding the first assembly  228  and the second assembly  230 . Thus, the placement of discrete parts  206  on the first web  212  in the first intermediate zone  290  or the second web  220  in the second intermediate zone  296  may be implemented with any of the embodiments discussed herein.  
         [0073]     Note that the turnbars mentioned herein, turn the first web second web or the single web in perpendicular directions. However, a turnbar may turn a web at any given angle provided that the first assembly and the second assembly are given enough distance between each other. Specifically, there must be enough distance between the longitudinal centerlines of each web allowing the first assembly and the second assembly to have sufficient space to turn their respective webs in the positive y direction and the negative y direction. Sufficient distance between the assemblies is required such that the first and second assemblies can periodically overlap one another thereby allowing their respective webs to receive the material  34  across their transverse width.  
         [0074]     The devices described herein for diverting, turning, redirecting, or inverting a web have included turnbars and idlers. Despite this description, any suitable methods of diverting, turning or redirecting a web known in the art can be used in conjunction with the present invention. Also, any suitable methods of inverting a web known in the art may be used in conjunction with the present invention.  
         [0075]     All embodiments mentioned within the specification are not constrained to the application of a material across the entire transverse width of the first web, second web, or single web. The material application may be across only a portion of the transverse width of the first web, second web, or single web. Also, the material application is not constrained to beginning at the leading edge of the first web, second web, or single web and is also not constrained to ending at the trailing edge of the first web, second web, or single web.  
         [0076]     All documents cited in the Detailed Description of the Invention are, in relevant part, incorporated herein by reference; the citation of any document is not to be construed as an admission that it is prior art with respect to the present invention.  
         [0077]     While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.

Technology Category: 4