Abstract:
A flying web splice apparatus and method for splicing a moving web of material to another web of material without tape or adhesives being used at the splice. Two splicer assemblies are provided which each have a rotatable parent roll feeding web material into the splicer apparatus. Each splicer assembly has a series of substantially parallel vacuum belts and a series of vacuum boxes therein. The vacuum boxes for each splicer assembly are evacuated by a vacuum blower, which creates a vacuum causing a suction through holes within a portion of the vacuum belts in order to hold web material to the vacuum belts. The series of belts for each splicer assembly are preferably rotatable about a top pivot to bring a bottom portion of each series of belts together. Preferably, at the bottom portions of each series of belts is located a pressure bonding mechanism, such as a series of ply-bond wheels, which bond the webs of material together when the bottom portions of the series of belts are brought together (preferably via one or more actuators). A stationary web from a parent roll is first placed over holes in one of the vacuum belts, which is then driven by a motor to drag the vacuum belt and web along part of its belt path and toward the pressure bonding mechanism. By the time the initially-stationary web reaches the actuated pressure bonding mechanism, the initially-stationary web is at the speed of the initially-moving web and can be precisely spliced thereto.

Description:
This application is a continuation application of U.S. patent application Ser. No. 09/119,367, filed on Jul. 20, 1998, now U.S. Pat. No. 6,051,095. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to the field of web splicing, and more particularly, to the field of web splicing equipment for joining the ends of sheet material such as paper. 
     BACKGROUND OF THE INVENTION 
     The process of splicing a sheet (or “web”) of material to another sheet of material is a common operation in a number of industries. In particular, in many paper industries, it is necessary to splice two webs of paper together in order to maintain a single unbroken web. This splicing operation is necessary for efficient operations downstream of the splicing equipment, which are fed with a steady and uninterrupted stream of web material. To maximize the efficiency of downstream operations, it is desirable to feed the web in a fast and steady manner without stopping or considerably changing the web speed. Conventional web splicing equipment is relatively inefficient, typically requiring the operator to stop the web or to significantly reduce web speed to splice the two ends of material. 
     In an effort to compensate for these inefficiencies, several conventional web splicing systems employ a variety of methods and assemblies to keep the web speed fed to downstream systems as fast and as continuous as possible. For example, as web material from an almost-expended roll (the “running roll”) is fed at normal operating speed, certain systems will gradually bring a fresh roll of material (the “ready roll”) up to the same speed, at which time the two webs are brought together and spliced. Such a system is disclosed in U.S. Pat. No. 3,252,671 issued to Phillips, Jr. et al. A drawback of such a system is that a large amount of web material which is fed through the splicer prior to the time the web speeds are matched is wasted during each splicing operation. 
     Other conventional web splicing systems perform their splicing operations by bringing the web from the ready roll up to speed very quickly. Such a system is disclosed in U.S. Pat. No. 5,252,170 issued to Schaupp. By bringing the ready roll web up to speed quickly, the material waste just described is avoided. However, systems which operate in this manner limit the types of web material which can be spliced. Many types of web material including, without limitation, toilet paper and tissue paper, are relatively low weight, low strength, and/or high stretch materials. Splicing operations performed by high-acceleration splicers on such materials perform poorly, and often result in ruptured webs or weak splices which are unable to withstand the rigors of downstream web operations. 
     Another disadvantage of many conventional web splicing systems (such as the one just described) is the manner in which the web splice is made. In particular, webs are often spliced by taping the ends of the two webs together. Especially in systems where the spliced area experiences a high amount of tension and/or in which the splicer does not provide a good speed match between the webs being spliced, a taped splice is often necessary. However, taped splices are undesirable because the spliced section of the web must eventually be removed from the web (for example, prior to the packaging of the final product) or the end products having the taped splice are must be discarded. Either method of discarding the tape spliced product section represents a waste of product. Furthermore, many tape splice systems require the operator to manually tape the two webs together. Not only does this typically require a section of both webs to be stationary for a period of time, but this is a labor-intensive inefficiency which is realized every time a splice is made. 
     As yet another example of how conventional web splicing systems attempt to feed downstream operations with a fast and continuous stream of web material through web splicing operations, certain systems use a bank of festoons or idler rolls immediately downstream of the splicer system. One such system is disclosed in U.S. Pat. No. 5,360,502 issued to Andersson. The festoon or idler rolls in such systems are adjusted to accommodate a significant amount of web material during normal web operations. When a web splicing operation is performed, the festoons or idler rolls move to release the web material wound therein. This process permits the web speed at the splice position (upstream of the festoons or idler rolls) to be temporarily reduced or stopped while the speed of the web material downstream of the festoons or idler rolls (i.e., for downstream machinery), is kept constant or only slightly reduced. When the splicing operation is complete, the web material passing the splicing area is brought back up to the speed of the web downstream of the festoons or idler rolls. A significant disadvantage of the web splicing system just described is the need for one or more banks of festoons or idler rolls and control elements and assemblies required for their operation. These components increase cost, maintenance, and floorspace requirements. Furthermore, it is of critical importance that a constant tension is maintained on the web throughout each operation performed upon the web. If constant tension is not maintained, web wrinkling and (in severe cases) web rupture can occur. Each festoon roll or idler roll added to a system creates web wrinkling and tensioning problems. Systems which attempt to address these problems by employing driven rolls in the bank of idler or festoon rolls inevitably introduce more expense, complexity, and maintenance costs into the system. 
     In view of the disadvantages of conventional web splicing systems noted above, there exists a need for a web splicing apparatus and method which can splice light weight, low strength, and high stretch web material without reducing the downstream speed of the web, which does not require additional elements or subsystems (e.g. a bank of festoon or idler rolls) to accommodate excess web material downstream of the splicer, and which can quickly and accurately accelerate a web up to the speed of a running web without the need for a taped splice and without the danger of web rupture during the splicing operation. The present invention provides such an apparatus and method. 
     SUMMARY OF THE INVENTION 
     An apparatus and method are provided for bonding one web of material (an “initially stationary web”) to a moving web of material (an “initially moving web”) without causing web rupture or web wrinkling. In order to quickly bring the initially stationary web up to the splicing speed without the need for slowing or stopping the initially moving web, the present invention employs a vacuum assembly which holds, pulls, and gradually accelerates the initially stationary web. The vacuum assembly preferably includes a first series of vacuum belts positioned to run around a series of pulleys. Within each vacuum belt is a at least one vacuum box. A vacuum is created within each vacuum box by a vacuum blower connected thereto. Each vacuum box preferably has an open face running behind a length of the corresponding vacuum belt&#39;s path. A number of holes in a length of each vacuum belt preferably pass across the open face of the underlying vacuum boxes as the belts runs their paths, thereby temporarily creating suction through the holes which acts to hold web material to the first series of vacuum belts. 
     The tail of the initially stationary web is first placed over the vacuum belt holes, which are themselves initially positioned over the open faces of the vacuum boxes at their top ends. To ensure precise and controlled positioning of the vacuum belts (as well as to determine their speed), the vacuum belts are preferably toothed timing belts. The suction created through the holes by rile vacuum within the vacuum boxes holds the tail of the initially stationary web to the vacuum belts. When the splicing operation is begun, a belt motor turns the vacuum belts, which pulls the attached initially stationary web along a length of the vacuum belt path. The length over which the accelerating web is held allows for a gradual web acceleration and prevents web rupture. 
     A second series of vacuum belts and a corresponding second vacuum assembly preferably faces the first series of vacuum belts and corresponding first vacuum assembly. The second series of vacuum belts and corresponding second vacuum assembly is substantially the same in structure and operation as the first series of vacuum belts. To eliminate the need for web taping or web adhesive in the splicing operation, a pressure bonding mechanism is preferably located at the bottom portions of both the first and the second series of vacuum belts. Preferably, the pressure bonding mechanism is a series of ply-bond wheels attached for rotation at the bottom portions of the belts. Both series of vacuum belts and corresponding vacuum belt assemblies are preferably mounted to rotate about a top portion of the respective vacuum belts, thereby bringing the ply-bond wheels at the bottoms of both series of vacuum belts together. By the time the initially stationary web has been pulled by the first vacuum belts to the bottom of the path traveled by the belts, the bottoms of both series of vacuum belts have preferably been pushed or pulled together by one or more actuators. By this same time, the initially stationary web held to the first series of vacuum belts has reached the speed of the initially moving web, and can reliably be spliced to the initially moving web by passing both webs through the ply-bond wheels. As the holes holding the initially stationary web to the first series of vacuum belts reach the bottom of the path followed by the first series of vacuum belts, the holes pass from the open front face of the vacuum boxes, thereby releasing the initially stationary web to the adjacent ply-bond wheels. For more precise bonding, a primary actuator is preferably employed to move the bottoms of both series of vacuum belts and ply-bond wheels to a close position with respect to one another, while a series of fast secondary actuators are employed to push the ply-bond wheels together when the web sections to be spliced are reached. When the web sections to be spliced have passed through the ply-bond wheels, the secondary actuators and the primary actuator are retracted. Preferably at a time just prior to this, a cutting blade is actuated to sever the initially moving web near the top of the second series of vacuum belts. At this time, the holes within the second series of vacuum belts are located at the top of the second series of vacuum belts and hold the trailing end of the severed web as it proceeds down the second series of vacuum belts and between the ply-bond rolls. 
     To further assist the initially stationary web to come up to the speed of the initially moving web without rupturing, an idler roll immediately upstream of the first series of vacuum belts is preferably driven temporarily by a motor through a clutch. By driving the idler roll in this manner, the initially stationary web is not required to overcome the rotational inertia of the idler roll. 
     Typically, the two webs to be spliced are unwound from parent rolls which have high inertias. Therefore, the apparatus and method of the present invention preferably includes a dancer roll and substantially vertical dancer track located between each parent roll and the corresponding vacuum belts. Each dancer roll is preferably slidable within its associated dancer roll track, and has one of the two webs of material passed therearound. By moving the dancer roll up or down within the dancer roll track, the amount of material being passed to and from the dancer roll preferably increases and decreases, respectively. Dancer roll sensors are preferably used to detect the location of each dancer roll within its dancer roll track, and preferably provide this information to a controller which controls the rotational speed of the parent rolls. In this manner, excess web material can be accumulated by a dancer roll just prior to the acceleration of an initially stationary web and can be controllably released as the parent rolls driven up to splicing speed. This allows the end of the initially stationary web to quickly accelerate as described above while providing the slower parent roll enough time to come up to splicing speed. Similarly, at the end of the splicing process when one parent roll is decelerating, the dancer roll can be moved to take up the web unwinding during parent roll deceleration. 
    
    
     More information and a better understanding of the present invention can be achieved by reference to the following drawings and detailed description. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention is further described with reference to the accompanying drawings, which show preferred embodiments of the present invention. However, it should be noted that the invention as disclosed in the accompanying drawings is illustrated by way of example only. The various elements and combinations of elements described below and illustrated in the drawings can be arranged and organized differently to result in embodiments which are still within the spirit and scope of the present invention. 
     In the drawings, wherein like reference numerals indicate like parts: 
     FIG. 1 is a sectional view of a first preferred embodiment of the splicer apparatus according to the present invention at a first stage of the apparatus&#39;s operation. 
     FIG. 2 is a sectional view of the apparatus shown in FIG. 1, with the apparatus in a second stage of the operation. 
     FIG. 3 is a sectional view of the apparatus shown in FIG. 1, with the apparatus in a third stage of operation. 
     FIG. 4 is a sectional view of the apparatus shown in FIG. 1, with the apparatus in a fourth stage of operation. 
     FIG. 5 is a sectional view of the apparatus shown in FIG. 1, with the apparatus in a fifth stage of operation. 
     FIG. 6 is a top view of the vacuum belt of the present invention. 
     FIG. 7 is a side view of the vacuum belt shown in FIG.  6 . 
     FIG. 8 is a sectionalized view of a portion of the vacuum belt shown in FIGS. 6 and 7, taken along section VIII—VIII of FIG.  7  and showing the vacuum holes of the vacuum belt. 
     FIG. 9 is a perspective view of a portion of the splicer apparatus according to a second preferred embodiment of the present invention. 
     FIG. 10 is another perspective view of a portion of the splicer apparatus according to the second preferred embodiment of the present invention. 
     FIG. 11 is an enlarged view of a portion of the splicer apparatus according to a third preferred embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     A) Structure of the First Preferred Embodiment 
     A first preferred embodiment of the present invention is shown in FIGS. 1-8. With reference first to FIG. 1, the splicer apparatus of the present invention (designated generally at  10 ) preferably includes two substantially identical splicer assemblies  12  and  14 . In FIG. 1, one web of material  16  is shown running from a parent roll  18  through the splicer assembly  12  and out to downstream machinery (not shown), while another web of material  20  is shown in a stationary position leading from parent roll  22  into the splicer assembly  14  where it terminates. FIGS. 1-5 illustrate the case where one parent roll  18  being unwound is almost depleted, and a fresh parent roll  22  is ready to be spliced onto the web  16  of the parent roll  18 . Of course, the operations shown in the figures can be performed at times which are different from the particular instance shown. For example, the almost depleted roll can instead be the parent roll  22 , while the fresh roll can be the parent roll  18 . Also, the splicing operations according to the present invention need not necessarily be performed when one parent roll is almost depleted and the other is fresh. As long as there is sufficient web material on both webs to complete the splicing operation described in more detail below, the splicing operation can be performed at any time. 
     With particular reference to FIG. 1, the parent rolls  18  and  22  are both mounted for rotation in a conventional manner upon roll mounts  24  and  26 , respectively, and are driven by motors  28  and  30  also in a conventional manner. The webs  16  and  20  extending from each of parent rolls  18  and  22 , respectively, run up to and over idler rolls  32  and  34 , under dancer rolls  36  and  38 , over idler rolls  40  and  42 , and then over idler rolls  44  and  46 , respectively. Each idler roll  32 ,  34 ,  40 ,  42 ,  44  and  46 , is positioned and secured for rotation in a conventional manner. Dancer rolls  36  and  38  are preferably supported by their ends within substantially vertical tracks  48  and  50 , respectively, which are themselves supported in place and permit upward and downward movement of dancer rolls  36  and  38  in a conventional fashion within vertical tracks  48  and  50 . 
     The splicer assemblies  12  and  14  are each provided with a vacuum assembly, (indicated generally at  52  and  54 , respectively). Vacuum assembly  52  preferably has the following components (only one of each which are shown in the Figures): a series of vacuum belts  56  running around a series of upper pulleys  58  and lower pulleys  60  which are mounted on a respective upper shaft  62  and lower shaft  64 ; a series of vacuum boxes  66 —one box supported within and underlying each vacuum belt  56 ; a belt motor  68  rotatably driving upper shaft  62  via a drive belt  70 ; and a vacuum blower  72  connected to each vacuum box  66  via vacuum hoses  74 . Vacuum assembly  54  similarly preferably comprises substantially identical components (i.e., a series of vacuum belts  76 , upper pulleys  78 , and lower pulleys  80 , an upper shaft  82 , a lower shaft  84 , a series of vacuum boxes  86 , a belt motor  88 , a drive belt  90 , a vacuum blower  92 , and a series of vacuum hoses  94 ) arranged and connected in a fashion similar to the corresponding components in the vacuum assembly  52 . 
     Each vacuum belt  56 ,  76  is preferably made of a wear-resistant material such as polyurethane, engineered plastic, etc., and is preferably provided with a series of holes  96  through a section of its length (see FIGS.  6 - 8 ). By virtue of its mounting arrangement over the upper and lower pulleys  58 ,  78  and  60 ,  80 , respectively, a space exists between the facing lengths of each vacuum belt  56 ,  76 . Within this space is located a vacuum box  66 ,  86  as indicated above. Each vacuum box  66 ,  86  preferably comprises an elongated channel-shaped element having closed ends and a open front face  98 ,  100 . The open front face  98 ,  100  of each vacuum box  66 ,  86  is positioned to directly underlie the underside of each corresponding belt as shown in FIG.  1 . Each vacuum box  66 ,  86  therefore has defined within its walls and the overlying vacuum belt  56 ,  76  a vacuum chamber  102 ,  104 , respectively. To ensure a better seal between the sides of each vacuum box  66 ,  86  and each corresponding vacuum belt  56 ,  76 , an elastomer seal (not shown) can be attached to and run around the open front faces  98 ,  100  of each vacuum box  66 ,  86 . Therefore, as the vacuum belts  56 ,  76  run across the open front faces  98 ,  100  of the vacuum boxes  66 ,  86  (described in more detail below), the vacuum chambers  102 ,  104  in each vacuum box  66 ,  86  are substantially sealed. Each vacuum box  66 ,  86  is connected via the series of vacuum hoses  74 ,  94  (preferably, one vacuum hose per vacuum box) to the corresponding vacuum blowers  72 ,  92  in a conventional fashion. Specifically, each vacuum box  66 ,  86  is provided with an opening  106 ,  108  over which the vacuum hoses  74 ,  94  are attached, respectively. This attachment permits the vacuum blowers  72 ,  92  (when activated) to evacuate air from vacuum boxes  66 ,  86 , thereby creating a vacuum within each vacuum box  66 ,  86 . The vacuum created helps to maintain a seal between each vacuum belt  56 ,  76  and the respective vacuum boxes  66 ,  86 . Preferably, the vacuum hoses  74 ,  94  are made of a flexible material to permit movement of the vacuum boxes  66 ,  86  with respect to the vacuum blowers  72 ,  92  as required (discussed below). Such vacuum hoses and their various materials are well known to those skilled in the art, and are therefore not described further herein. 
     The belt motors  68  and  88  preferably turn the drive belts  70  and  90 , respectively, which themselves rotate the upper shafts  62  and  82  and the upper pulleys  58  and  78  mounted thereon, respectively. The rotation of the upper pulleys  58  and  78  therefore turns the vacuum belts  56  and  76  in a manner well known to those skilled in the art. As will be described in greater detail below, the vacuum created within the vacuum boxes  66 ,  86  by the vacuum blowers  72 ,  92  causes a suction effect on the outer surface of the vacuum belts  56 ,  76  around the vacuum belt holes  96 . This suction pulls nearby web material firmly against the outer surface of the vacuum belts  56 ,  76  and permits the web material to be drawn along the length of the vacuum boxes  66 ,  86  as the belt motors  68 ,  88  turn the vacuum belts  56 ,  76 . 
     A ply-bond wheel  110  is preferably mounted for rotation between each of the series of vacuum belts  56  and corresponding lower pulleys  60  on the splicer assembly  12 . Similarly, a ply-bond wheel  112  is preferably mounted for rotation between each of the series of vacuum belts  76  and corresponding lower pulleys  80  on the splicer assembly  14 . At least one of the ply-bond wheels  110 ,  112  are preferably provided with a rough outer surface (e.g., a dimpled, knurled, or ribbed surface) which can be patterned to mesh with the ply-bond wheels  112 ,  110  on the facing splicer assembly  12 ,  14 . Alternately, the ply-bond wheels  110 ,  112 , can mesh with smooth ply-bond wheels  110 ,  112 , on the facing splicer assembly  12 ,  14 . 
     Actuators  114  and  116  are attached to the lower shafts  64  and  84  of the splicer assemblies  12  and  14 . The actuators  114  and  116  can be of any type well known to those skilled in the art, such as hydraulic or air cylinder actuators, electro-magnetic actuators, etc. The actuators  114  and  116  are also attached to a fixed point relative to the respective splicer assemblies  12  and  14 , and therefore can be actuated to pull or push the lower shafts  64 ,  84  of each splicer assembly  12 ,  14  to pivot the vacuum belts  56 ,  76  and vacuum boxes  66 ,  86  about the upper shafts  58  and  78 , respectively. This pivoting action acts to bring the ply-bond wheels  110  and  112  together when the actuators  114 ,  116  are extended (as noted below with respect to the operation of the present invention). 
     B) Operation of the First Preferred Embodiment 
     A sequence of operational stages for the first preferred embodiment of the present invention is illustrated in FIGS. 1-6. With reference first to FIG. 1, the webs  16  and  20  of the parent rolls  18  and  22 , respectively, are shown running through the idler rolls  32 ,  34 ,  40 ,  42 ,  44 ,  46  and the dancer rolls  36  and  38  as described above. The web  16  of the parent roll  18  is shown being run at normal operational speed from the parent roll  18  through the splicer apparatus  10  (between splicer assemblies  12  and  14 ) and to one or more pieces of downstream equipment (not shown). In this stage, the splicer apparatus  10  is essentially inactive, with the belt motors  68 ,  88 , the vacuum belts  56 ,  76 , the vacuum blowers  72 ,  92 , and the actuators  114 ,  116  being stationary. As the parent roll  18  is gradually depleted, a sensor  118  preferably monitors the size of the parent roll  18 . Simultaneously, during this stage, a dancer roll sensor  120  preferably monitors the location of the dancer roll  36  in the vertical track  48 . The position of the dancer roll  36  in the vertical track  48  is communicated to a controller (not shown) which is also in communication with and preferably independently controls the powered state and/or the speed of motors  28 ,  30 , the actuators  114 ,  116 , the vacuum blowers  72 ,  92 , and the belt motors  68 ,  88 . During the operational stage shown in FIG. 1, if the unwind speed of the parent roll  18  should increase beyond the speed of the web  16  in operations downstream of the splicer apparatus  10 , the extra slack within the splicer assembly  12  is taken up by a downward motion of the dancer roll  36  in the vertical track  48  until the motor  28  controlled by the controller has sufficient time to reduce the speed of the parent roll  18 . Similarly, if the unwind speed of the parent roll  18  should decrease below the speed of the web  16  in operations downstream of the splicer apparatus  10 , the excess tension exerted on the web  16  can be relieved by an upward motion of the dancer roll  36  in the vertical track  48  until the motor  28  controlled by the controller has sufficient time to increase the speed of the parent roll  18 . Because a light tension is desirable and slack in the web  16  is undesirable as discussed in the Background of the Invention above, the dancer roll  36  is preferably kept in a location near the top of the vertical track  48  during the stage shown in FIG.  1 . The operations just described to control the speed of the motor  28  by monitoring the amount of web  16  in the splicer assembly  12  via the position of the dancer roll  36  are well known to those skilled in the art and are not therefore discussed further herein. 
     When the parent roll  18  is reduced to a desired size (which can correspond, for example, to an almost-depleted state of parent roll  18 , a known break in the parent roll  18 , a desired amount of unwound web  16 , or a desired parent roll size), the sensor  118  preferably sends a signal to the controller to begin the splicing process. In the event that the end  122  of the web  20  from the fresh roll is ragged or damaged, the end may be cut off prior to this time in any convention manner well known to those skilled in the art. For example, a well known method of removing the uneven or ripped end of a roll is to manually cut across the width of the web with a roller having a V-shaped cross-section. The roller (not shown) presses the web to be cut against a long blade mounted along the width of the web (also not shown), thereby cutting the ragged web off to be discarded. Other manners in which the end of a web may be cut off and tools to accomplish this task are well known to those skilled in the art and fall within the spirit and scope of the present invention. 
     In the first step of the splicing process, the controller preferably determines the speed of the web  16  in the splicer assembly  12  (e.g., via sensor  118  or by other means well known to those skilled in the art). If necessary, and at the preference of the operator, the controller can send a signal to both the motor  28  turning the parent roll  18  and to the equipment downstream of the splicer apparatus  10  to slow the web  16  in a conventional manner to a desired splicing speed. 
     Second, the controller preferably sends a signal to turn on the vacuum blower  92  and another signal to the motor  30  to slowly turn the fresh parent roll  22  in a direction indicated by arrow A on FIG.  1 . In the operational stage shown in FIG. 1, the holes  96  of the vacuum belt  76  are located in the upper position indicated by bracketed area B on FIG.  1 . By turning the vacuum blower  92  on, the end  122  of the web  20  on the fresh parent roll  22  is secured by suction to a top area of the vacuum belt  76 . Therefore, when the motor  30  turns the fresh parent roll  22  in the direction indicated by arrow A on FIG. 1, any slack existing between the fresh parent roll  22  and the end  122  of the web  20  is wound up onto the fresh parent roll  22 . Also by this rotation, the web  20  elevates the dancer roll  38  to a top-most position in vertical track  50 . A dancer roll sensor  124  (similar to the dancer roll sensor  120  in the neighboring splicer assembly  12 ) preferably monitors the movement of the dancer roll  38  and sends a signal to the controller to indicate when the dancer roll  38  has reached the top-most position in the vertical track  50 , at which time the controller preferably sends a signal to the motor  30  to stop its rotation. Therefore, at the operational stage shown in FIG. 1, the web  20  of the fresh parent roll  22  is ready for the splicing operation. 
     It should be noted that the dancer rolls  36  and  38  in the present invention can be free-floating within vertical tracks  48  and  50 , respectively, thereby being fully vertically supported within the tracks by the webs  16  and  20 . However, it is preferred that the vertical tracks  48  and  50  provide a counterweight to the dancer rolls  36  and  38  to counter at least a portion of the dancer rolls&#39; weight. Roll counterweight systems and methods are well known to those skilled in the art, and are therefore not described in further detail herein. Also, the vertical position of the dancer rolls  36  and  38  in their respective vertical tracks  48  and  50  can be indexed and maintained as desired in a number of conventional manners. Therefore, for those operations described herein in which the location of the dancer rolls  36  and  38  are changed in order to take up or release web material, it should be noted that the positions of the dancer rolls  36  and  38  can be directly controlled by a controller. Such roll indexing systems are well known to those skilled in the art, and are therefore not described in further detail herein. 
     Next, the controller preferably sends a signal to the motor  30  to begin accelerating and rotating the fresh parent roll  22  in a direction indicated by arrow C on FIG.  2 . This motion creates slack in the web  20  which is taken up by the dancer roll  38  by being dropped to a lower position in the vertical track  50 . When the dancer roll sensor  124  detects that the dancer roll  38  has reached a low position within the vertical track  50 , the dancer roll sensor  124  preferably sends a signal to the controller to indicate this position has been reached. The controller then preferably sends a signal to the belt motor  88  to begin turning the upper shaft  82  and the vacuum belts  76 . The belt motor  88  accelerates quickly, and therefore quickly increases the speed of the vacuum belts  76  and the web  20  attached by suction action thereto. However, the speed of the vacuum belts  76  is gradually ramped over the entire vertical distance of the vacuum belts  76 , thereby providing for a relatively low tension force on the web  20  during the accelerating period. This gradual acceleration exerts less tensile force on the web  20  than instantaneous or short acceleration periods (which produce significant tension spikes during web acceleration). In order to further reduce the tension experienced by the web  20  during the acceleration on the vacuum belts  76 , the idler roll  46  (and the corresponding idler roil  44  on the opposite splicer assembly  12 ) is preferably driven by a motor through a clutch (not shown) which is engaged in a conventional manner by the controller at a time close to when the controller sends the signal to the belt motor  88  to begin turning the upper shaft  82 . The motor-driven idler roll  46  begins to turn and assists the movement of the web  20  over the idler roll  46 , rather than requiring the web  20  to overcome the rotational inertia of the stationary idler roll  46  when coming up to speed. By assisting the web  20  to move in this manner, the clutch and motor-driven idler roll  46  helps to prevent excess tension on the web  20  during splicing operations. After the web  20  comes up to speed as described below, the clutch on the idler roll  46  preferably disengages to leave the idler roll  46  once again unpowered. 
     As shown in FIG. 3, the web  20  from the fresh parent roll  22  is accelerated and dragged down the vertical length of the vacuum belts  76 . By the time the end  122  of the web  20  has reached the bottom of the vacuum belts  76 , the speed of web end  122  matches the speed of the running web  16 , the speed of both webs  16  and  20  near the vacuum belts  56 ,  76  being measured in a manner described below. To provide the fresh parent roll  22  enough time to also accelerate to the speed of web end  122 , the excess of the fresh web  16  earlier taken up by the dancer roll  38  in the vertical track  50  is released. This release can be performed by a lifting action exerted by the fresh web  20  upon the dancer roll  38 , which itself is caused by increased tensile force exerted upon the fresh web  20  in the acceleration of web end  122 . Alternatively, the release can be controlled primarily by a controller for the dancer roll as is known in the art. The web  20  released by the dancer roll  38  during the operational stage shown in FIG. 3 permits the parent roll  22  to come up to speed with the end  122  of the web  20 . 
     With continued reference to FIG. 3, at or at some time near when the belt motor  88  is instructed by the controller to begin turning, a signal is sent to the actuators  114  and  116  to extend to a position where the ply-bond wheels  110  and  112  are in contact with one another. Therefore, by the time the web end  122  of the fresh web  20  reaches the bottom of the vacuum belts  76 , the web end  122  has reached the web speed of web  16 , and the ply-bond wheels  110 ,  112  are in position to bond webs  16  and  20  together. Specifically, the actuators  114  and  116  exert a sufficient force compressing the ply-bond wheels  110 ,  112  together to bond the webs  16  and  20  which pass through the nip position between the ply-bond wheels  110  and  112 . It should be noted that because the nip position between the ply-bond wheels  110  and  112  is below the front open face  100  of the vacuum box  86 , the suction exerted through the holes  96  by the vacuum within the vacuum box  86  ceases by the time the web end  122  reaches the nip position, thereby releasing the web  16  from the vacuum belts  76 . In an alternative embodiment, the vacuum box  86  can extend to the nip and the vacuum can be shut off when desired. 
     It should be noted that other assemblies and methods (rather than ply-bond wheels  110 ,  112 ) can be used to bond the web  16 ,  20  together. For example, the ply-bond wheels  110 ,  112  can be replaced by two large pressure bonding rolls (not shown) positioned directly beneath the nip position of the vacuum belts  56 ,  76 . Alternately, continuous tracks can be similarly positioned to press the two webs  16 ,  20  together against a roll, another track, or any number of other surfaces to effectuate a pressed bond between the two webs  16 ,  20 . Also, two movable plates (also not shown) can be positioned immediately downstream of the vacuum belts  56 ,  76  to press and bond a section of the webs  16 ,  20  together. Alternate pressure-bonding systems and methods are well known to those skilled in the art and fall within the spirit and scope of the present invention. 
     By accurately measuring the speed of the web  16  just prior to the splicing operation and by measuring the speed to which the web  20  is ramped during the splicing operation, the speed of both webs  16  and  20  can be synchronized for precise splicing (by, for example, adjusting the speed of the belt motor  88  turning the vacuum belts  76 ). The speed of both webs  16  and  20  can be measured in a number of different ways. In the preferred embodiment of the present invention shown in the figures, each vacuum belt  56 ,  76  is preferably provided with timing teeth  150  along the edges of each vacuum belt  56 ,  76  (see FIG.  8 ). These timing teeth  150  are preferably detected, counted and timed by a conventional timing belt sensor (not shown) to determine the exact position of each vacuum belt  56 ,  76  as well as the speed of each vacuum belt. Other methods for detecting the position and speed of the vacuum belts  56 ,  76  can also be employed, such as by measuring the number of rotations of upper shafts  62 ,  82  and/or the lower shafts  64 ,  84  via a conventional sensor, by securing one or more speed sensors near the vacuum belts  56 ,  76  to directly measure the surface speed of the vacuum belts in a conventional manner, etc. These alternate methods for detecting the position and speed of the vacuum belts  56 ,  76  are well known to those skilled in the art and are therefore not described further herein. 
     In the next operational stage of the present invention illustrated in FIG. 4, the vacuum belts  76  continue to run around the upper pulleys  78  and the lower pulleys  80 , thereby moving the vacuum holes  96  in the vacuum belts  76  up the backside of the vacuum boxes  86 . Tis position of the vacuum belts  76  is detected by the timing belt sensor (not shown) as described above, which sends a signal at this time to turn the vacuum blower  92  on the fresh web side off and to turn the vacuum blower  72  on the depleted web side on. By turning the vacuum blower  92  off at this time, the fresh web  20  is prevented from attaching to the vacuum belt  76  once the holes  96  in the vacuum belts  76  again move into a location facing the web  20 . By turning the other vacuum blower  72  on at this time, after the web  16  of the depleted parent roll  18  has been severed (described below), the trailing end of the depleted parent roll  18  is held in place against the vacuum belts  56  by the suction created through the holes  96  in the vacuum belts  56 . This securement is performed once the holes  96  in the vacuum belts  56  are rotated to an upper position on the open front faces  98  of the vacuum boxes  66 . When this position is reached by the holes  96  in the vacuum belts  76  (once again measured by the timing belt sensor described above), a signal is preferably sent front the controller to a cutter  126  which is preferably rotatably secured at a location above and between the upper shafts  62 ,  82 . This signal causes the cutter to rotate and push the web  16  against a blade  128  located on the opposite side of the web  16 , thereby cutting the web  16  at this point. At this operational stage, a signal is also sent by the controller to the motor  28  to decelerate and stop the depleted parent roll  18 . Due to the fact that such a stop is not instantaneous, web material which continues to unwind from the depleted parent roll  18  after the web  16  has been cut is taken up by the dancer roll  36  as it is moved down along the track  48  under the weight of the dancer roll  36 . 
     It should be noted that though preferred, the process of securing the trailing end of the depleted parent roll  18  to the vacuum belt  56  is not required to practice the present invention. Specifically, the tail securement process just described can be left unperformed, with the trailing end of the depleted parent roll  18  being drawn between the ply-bond wheels  110 ,  112 . In this case, the vacuum belt  56  acts only to support the trailing end of the depleted parent roll  18  as is drawn between the ply-bond wheels  110 ,  112 . 
     In the final stage of the web splicing operation (see FIGS.  4  and  5 ), the fresh web  20  is continued to be drawn between the two splicer assemblies  12 ,  14  while the severed tail end of the depleted roll web  16  is drawn down between the ply-bond wheels  110  and  112  to be bonded to the fresh web  20 . After the tail end of the depleted roll web  16  has been bonded and has left the nip position between the ply-bond wheels  110  and  112  (this being preferably determined by the position of the vacuum belts  56 ,  76  in the manner described above), a signal is sent by the controller to the actuators  114  and  116  to retract, thereby pulling the lower shafts  64 ,  84  and the ply-bond wheels  110 ,  112  to their original spread positions (see FIG.  5 ). Also, the controller sends a signal to the vacuum blower  72  to turn the vacuum blower  72  off. Finally, the vacuum belts  56  and  76  are rotated to their original positions where the holes  96  in each vacuum belt set  56 ,  76  are positioned near the tops of the underlying vacuum boxes  66 ,  86 , respectively. Once again, the position of the vacuum belts  56 ,  76  is preferably detected by the timing belt sensors described above. 
     If necessary, the web speed of the fresh web  20  and the web  20  downstream of the splicer apparatus  10  can be brought up to speed in a conventional manner by the controller. The splicer apparatus  10  is now ready for the next splicing operation, which follows the same steps and operations as described above, but for corresponding elements and assenblies on the opposing splicer assembly  14 ,  12 . 
     Structure and Operation of the Second Preferred Embodiment 
     A second preferred embodiment of the present invention is illustrated in FIGS. 9 and 10. The splicer apparatus of the present invention according to the second preferred embodiment differs from the first preferred embodiment primarily in the elements, arrangement and operation of the vacuum assemblies ( 52  and  54  in the first preferred embodiment) and the actuators ( 114  and  116  in the first preferred embodiment). As seen in FIGS. 9 and 10, the upper shaft  62 ,  82 , lower shaft  64 ,  84  and vacuum box  66 ,  86  arrangement of the first preferred embodiment is replaced by two swing arms  202 ,  204  which are mounted to rotate on a frame  200  about their upper ends  206 ,  208  and which are attached at their lower ends  210 ,  212  by one actuator  214 . The actuator  214  is pivotably mounted on both ends in a conventional manner to lower ends  210 ,  212  of swing arms  202 ,  204 . The lower end  210 ,  212  of each arm  202 ,  204  is attached in a conventional manner (e.g., by a connector bar  216 ,  218 ) to the lower ends of a series of vacuum boxes  220 ,  222  similar to the vacuum boxes  66 , 86  described above with regard to the first preferred embodiment. The upper ends of each series of vacuum boxes  220 ,  222  are pivotably attached in a conventional manner to the frame  200 . As with the first preferred embodiment, vacuum belts  224 ,  226  (not shown for purposes of clarity in FIGS. 9 and 10) run around each vacuum box  220 ,  222 , respectively, and operate in a manner much the same as the vacuum belts  56 ,  76  of the first preferred embodiment. Ply-bond wheels  228 ,  230  are rotatably mounted to the connector bars  216 ,  218  in a conventional fashion. For clarity purposes, only two of the ply-bond wheels  228 ,  230  are shown in FIG. 9 to illustrate the location and orientation of the ply-bond wheels  228 ,  230 . 
     With the vacuum assemblies thus arranged, when the controller (not shown) sends a signal to bring the ply-bond wheels  228 ,  230  together as in the first preferred embodiment, preferably one actuator  214  draws the lower ends  210 ,  212  of the swing arms  202 ,  204  and the connector bars  216 ,  218  together as shown in FIGS. 9 and 10. The motion of swing arms  202 ,  204  and the vacuum boxes  220 ,  222  during this operation is indicated by the arrows labeled D in FIG.  10 . Because the lower ends  210 ,  212  of the swing arms  202 ,  204  and the lower ends of each vacuum box  220 ,  222  are also attached to the connector bars  216 ,  218 , respectively, the lower ends  210 ,  212  of the swing arms  202 ,  204  and the lower ends of the vacuum boxes  220 ,  222  also move together. To ensure that one swing arm  202 ,  204 , connector bar  216 ,  218 , and series of vacuum boxes  220 ,  222  do not swing more than the other swing arm  204 ,  202 , connector bar  218 ,  216 , and series of vacuum boxes  222 ,  220 , the top of each swing arm  202 ,  204  is provided with an extension  232 ,  234 . The two extensions  232 ,  234  meet in between the upper pivot points of the swing arms  204 ,  202 . The extension  234  of one swing arm  204  has an end with a round profile. The extension  232  of the other swing arm  202  has an end with a C-shaped profile sized to accept the round profile of the mating extension  234 . When the swing arms  202 ,  204  rotate, the round profile of the extension  234  pivots within the C-shaped profile of the mating extension  232 , thereby maintaining an even movement of the swing arms  202 ,  204  (and the vacuum boxes  220 ,  222  and connector bars  216 ,  218 ) when the actuator  214  is operated to bring the ply-bond wheels  228 ,  230  together or to spread them apart. 
     It will be appreciated by one having ordinary skill in art that other interlocking configurations (e.g., other profile and extension shapes, locations and relationship of extensions, etc.) can be employed to ensure that each vacuum assembly moves an equal distance under the pull or push of actuator  214 . 
     Structure and Operation of the Third Preferred Embodiment 
     A third preferred embodiment of the present invention is illustrated in FIG. 11, and differs from the second preferred embodiment described above and illustrated in FIGS. 9 and 10 in the addition of two batteries of secondary actuators  302  and  304  to the splicer apparatus. For purposes of clarity, only the left swing arm  300 , and vacuum boxes  301  are shown in FIG.  11 . 
     To increase the efficiency of the present invention, it is desirable to actuate the ply-bond wheels  306  for a very precise period of time. If the ply-bond wheels  306  are actuated for too long of a period of time, undesirable marks can be created by the ply-bond wheels  306  on web material outside of the sections of web material intended to be spliced. If the ply-bond wheels  306  are actuated for too short a period of time, splice quality can suffer, resulting in a poor or unsuccessful splice. Therefore, it is preferred to employ secondary actuators  302  in the splicer apparatus (in addition to a primary actuator  310  which is similar to the actuator  214  used in the second preferred embodiment). In the third preferred embodiment of the present invention illustrated in FIG. 11, the ply-bond wheels  306  are directly actuated by one or more secondary actuators  302 . Specifically, each ply-bond wheel  306  is preferably mounted on a common bar  313  positioned adjacent the secondary actuators  302 . One end of each of the secondary actuators  302  can be mounted directly to a common support  315  moved by the primary actuator  310  while the other ends of the secondary actuator  302  actuate the common bar  313 . Alternatively, individual bars may be used for each secondary actuator  302  as desired. Just prior to the splicing operation, the primary actuator  310  is preferably activated by the controller (not shown) in a manner similar that described in the first and second preferred embodiments above. The primary actuator  310  pulls the ply-bond wheels  306  and the bottoms of the vacuum belts (not shown for clarity) to a close position with respect to one another. Upon reaching this position, and when the time has come to begin ply-bonding the webs of material, passing between the ply-bond wheels  306 , the controller preferably sends a signal to the secondary actuators  302 . The secondary actuators  302  respond by quickly extending, thereby pushing the common bars  310  and the attached ply-bond wheels  306  towards one another. When it is desired to cease the ply-bonding operation, the controller preferably sends another signal to the secondary actuators  302  to quickly retract, pulling the common bars  310  and the attached ply-bond wheels  306  away from one another and the webs of material. 
     By employing a primary actuator  310  to move the vacuum belts and the ply-bond wheels  306  to a ready position and a series of fast secondary actuators  302  to quickly extend and retract to complete the ply-bonding operation, very precise ply-bonding can be achieved. In particular, the result of such a design is that ply-bonding marks which are necessary for the web bonding operation are only found on those portions of both webs to be bonded (no more web and no less web is affected). 
     The embodiments disclosed above and illustrated in the figures are presented by way of example only and are not intended as a limitation upon the concepts and principles of the present invention. As such, it will be appreciated by one having ordinary skill in the art that various changes in the elements and their configuration and arrangement are possible without departing from the spirit and scope of the present invention as set forth in the appended claims. 
     For example, it will be appreciated by one having ordinary skill in the art that any number of vacuum belts  56 ,  76  can be arranged on each splicer assembly  12 ,  14 , respectively. The vacuum belts  56 ,  76  need not all be of the same width or shape. In this regard it should be noted that the vacuum boxes  66 , 86  underlying the vacuum belts  56 ,  76  can be of any shape or size and preferably match the shape and size of the vacuum belts  56 ,  76 . A splicer assembly employing a very small number of vacuum belts  56 ,  76  (e.g., one, two, or three belts) could also employ a similarly smaller number of vacuum boxes  66 ,  86 . Also, such a splicer assembly would necessarily have a limited number of ply-bond wheels,  110 ,  112  according to the splicer assembly design described above. However, in such a case, it would be preferred to mount more (or all) ply-bond wheels  110 ,  112  for rotation on a separate shaft rather than on lower shafts  64 ,  84 . Such an arrangement would require a connection between the separate ply-bond wheel shaft and the lower shafts  64 ,  84  in order to maintain the ply-bond wheels  110 ,  112  at a surface speed equal to the vacuum belt speed and to keep the ply-bond wheels  110 ,  112  in line with the lower ends of the vacuum belts  56 ,  76  during splicing operations. Alternate arrangements such as that just described fall within the spirit and scope of the present invention. 
     As another example of various apparatus arrangements and components which fall within the breadth of the present invention, the particular drive system which is described above and illustrated in the drawings need not necessarily consist of the particular elements and arrangement disclosed. In particular, a number of conventional methods and systems exist for rotating the upper shafts  62 ,  82  instead of the belt motor  68 ,  88  and drive belt  70 ,  90  arrangement disclosed. The upper shafts  62 ,  82  can be driven by an in-line motor, by a gear train, or by a number of other systems and methods which are well-known to those skilled in the art and which therefore are considered to fall within the spirit and scope of the present invention. Additionally, though the upper shafts  62 ,  82  are the driven shafts as disclosed, it is possible to instead drive the lower shafts  64 ,  84  in a similar fashion. In fact, it can be desirable to drive both the upper shafts  62 ,  82  and lower shafts  64 ,  84  in a manner similar to that disclosed in the present application. Also, Per than employ upper pulleys  58 ,  60  lower pulleys  78 ,  80 , the vacuum belts  56 ,  76  can be wound around a non-slip surface of upper shafts  62 ,  82  and lower shafts  64 ,  84 , or can be provided with a non-slip material on the underside of the vacuum belts  56 ,  76  which contacts and rides upon upper shafts  62 ,  82  and lower shafts  64 ,  84 . Alternately, the vacuum belts  56 ,  76  can be provided with holes (or teeth) with mesh with teeth (or holes) within upper pulleys  58 ,  60  and lower pulleys  78 ,  80  around which the vacuum belts  56 ,  76  run. These and other belt driving arrangements and methods are well-known to those skilled in the art and are also considered to fall within the spirit and scope of the present invention. 
     Although the embodiments of the present invention disclosed above have a set of holes  96  located in a particular location on the vacuum belts  56 ,  76 , it will be appreciated by one having ordinary skill in the art that a number of hole arrangements and locations are possible and can achieve the desired results of the splicer apparatus. For example, it is possible to have a series of holes  96  which are located entirely along the length of the vacuum belts  56 ,  76 . In this arrangement, the desired release and/or capture of the webs  16 ,  20  on the vacuum belts  56 ,  76  at their designated times (see the description above) could be facilitated in other manners, such as by turning off or turning on the vacuum blowers  72 ,  92  at precise times, etc. Other hole patterns and arrangements matching, for example, various vacuum box  66 ,  86  configurations or belt shapes are also possible. Such alternative arrangements are well-known in the art and therefore also fall within the spirit and scope of the present invention. 
     Finally, it will be appreciated by one having ordinary skill in the art that the sensors utilized in the embodiments described above and illustrated in the figures can be of a variety of types commonly known in the art, such as motion sensors, light sensors, etc. Also, rather than employ sensors, it is possible (though not preferred to visually monitor any or all of the objects monitored herein by sensors and to control the operations of the splicer apparatus  10  manually rather than by use of a controller.