Abstract:
A method and apparatus are provided for automatic and hands-free threading of an elastomeric mix into a calender set of rolls comprising one or more pairs of rolls that have a nip between them. A wedge is provided with a tip that is positioned downstream from the nip and at a predetermined distance from the nip. As the rolls of the nip are rotated, the tip of the edge removes all, or a desired portion of, the elastomeric mix from a first roll of the nip so as to transfer the elastomeric mix to a second roll of the nip. The tip of the wedge may be placed into contact with the first roll. The wedge may also have an arcuate surface, shaped e.g., like the outer surface of the first roll, and positioned a predetermined distance from the outer surface of the first roll.

Description:
FIELD OF THE INVENTION 
       [0001]    The subject matter of the present disclosure relates generally to a method and apparatus that allow for automatic and hands-free threading of an elastomeric mix into a calender set of rolls comprising one or more pairs of rolls that have a nip between them. 
       BACKGROUND OF THE INVENTION 
       [0002]    Calenders are mechanisms that include a series of pairs of rolls through which a substance that is malleable can be run in order to smooth out the material and form a skim or sheet of uniform thickness. In the tire industry, calenders are used to process an elastomeric or rubber mix that is usually extruded and then sent through the calender to create a sheet of rubber or elastomer mix. Between each pair of rolls is a gap or nip through which the material is run as the rolls are rotated. Depending on a host of processing variables, the sheet will assume some thickness that is proportional to the width of the nip. Often, the material is fed through three sets of rolls and nips in order to create a homogenous and smooth sheet that also has a desired thickness, as is the case for an inverted “L” configured calender as will be described shortly. This sheet is then used to create some portion of the tire, such as the tread or other semi-finished goods used to manufacture and assemble the tire such as belts and carcass plies, etc. 
         [0003]    An illustration of such a typical calendering system  10  is shown in  FIGS. 1 and 2 , which has three pairs of rolls (labeled as rolls  12 ,  14 ,  16 , and  18 ) with a nip between pairs as well as a fifth roll  20 , sometimes referred to as a take-off roll, that takes the sheet as it comes off the fourth roll  18 . The purpose of this roll  20  is to provide tension to remove the sheet  22  as it exits the calender. The calender rolls that are part of a pair rotate in opposite directions or in the same linear direction/surface direction in the nip area  24  so that material that is fed into the entrance  26  of the nip is forced through the nip into the exit area  28  of the nip. For the first pair of rolls, the entrance of the nip is located above the rolls so that material is naturally fed into the nip via gravity upon startup or just before. Usually, a bank  30  of kneaded material (sometimes referred to as a bourelet by the inventor(s)) collects above the nip of the first pair of rolls so that enough material is present to form an uninterrupted sheet of material that can pass through the calendering system. This bank is created by oversupplying slightly the amount of material needed to create the sheet of material from a source of the material such as an extruder. In time, material is forced downward into the nip by the rotation of the rolls. 
         [0004]    After exiting the first nip area  24   a,  the material then winds in a counterclockwise direction around the second roll  14  until it is reaches the third roll  16  where it goes through a second nip area  24   b.  Once it exits, the material then winds in a clockwise direction around the third roll  16  and then encounters the fourth roll  18  where it goes through the third nip area  24   c.  At this point, the sheet then attaches to the fourth roll  18  where it is rotates in a counterclockwise direction once more around the bottom and part of the back of the fourth roll  18  and on top of the fifth roll  20 , which is rotated in the clockwise direction and which is biased upwards to place the sheet in tension before it proceeds to a production center where some tire component is made using the sheet of material. This desired path is shown by the solid outline of material whereas an unintended circulation of material is represented by the dashed arrows as will be described in further detail later. 
         [0005]    All the rolls or pairs of rolls can be commonly driven by a single motor using gears, chains, or belts. In such a case, the speed of all the rolls or of the rolls of a pair can be the same or can be different utilizing some sort of transmission system such as a variable speed ratio reducer between the rolls and the motor. Alternatively, all the rolls can be independently driven using a separate motor for each roll. In that case, electronic controls are sometimes furnished that allow tight and independent control of the speed of each roll by way of suitable programming by the operator or some other control algorithm executed by a computer. For example of rolls that are independently driven or that can operate at different adjustable speeds. See, e.g., U.S. Pat. Nos. 2,333,629; 4,444,361; and G.B. Pat. Nos. 856,454; 620,340. 
         [0006]    An example of a production center that can be fed by a calender system is depicted by  FIG. 3 , which is disclosed in U.S. Patent Application Publication No. 20110036485, which is commonly owned by the assignee of the present invention and whose content is incorporated by reference for all purposes in its entirety. Portions of that application are reproduced herein as follows to describe how the process works and how it can be used in conjunction with the present invention. It should be noted that this is given by way of an example of a production center and that the present invention is equally applicable to any manufacture of a tire component that requires a calendering system of any sort including those that only have a single pair of rolls. 
         [0007]    A system  110  for generating a multi-layered tire component in accordance with the methods described in the &#39;485 application is generally shown in  FIG. 3 . System  110  generally operates to form a multi-layered tire component by winding strips  141  about a building surface. Because a tire component is a wound product, it generally forms a complete circle (i.e., a ring). The component is also referred to herein as a band. Also, system  110  generates a sheet  121  from which the strips  141  are formed, and, in particular embodiments, the sheet  121  remains continuous as it travels along a closed-loop path to and from a sheet generator  120 . Accordingly, system  110  automatically returns any unused sheet material for reuse by generator  120 . System  110  generally forms elastomeric tire components, such as, for example, tread, sub-tread, and cushion gum. It can also create a multi-layered band that is a profiled tire tread band. 
         [0008]    In this embodiment, system  110  comprises a sheet generator  120 , a cutting assembly  140 , a strip applicator assembly  160 , a recovery assembly  170 , and a programmable logic control (not shown). System  110  may also include a roll assembly  130  for directing a sheet  121  from generator  120  to cutting assembly  140 . Sheet generator  120  generally transforms input material  112  into a sheet  121 , which is ultimately cut into strips  141  by cutting assembly  140 . 
         [0009]    With continued reference to  FIG. 3 , input material  112  is received through inlet  122 , and may comprise new material  112   a  and/or previously used material  112   b  supplied by recovery assembly  170 . After receiving input material  112 , generator  120  forms the input material by any known means such as by a calendering system shown in  FIGS. 1 and 2  and described above into sheet  121 , where sheet  121  is formed to any desired width and thickness. Sheet  121  is expelled from generator  120  by way of outlet  123 . 
         [0010]    In one embodiment, as shown in  FIG. 3 , generator  120  comprises an extruder. Extruders generally push input material  112  through a die or head, such as by way of a screw. Any extruder known to one of ordinary skill in the art may be used by system  110 . Generator  120  may also comprise a calender in lieu of, or in addition to, an extruder, which may comprise a pair of rolls positioned in close proximity to each other to form a gap or nip, through which input material  112  passes to from a sheet  121  (as described above). The resulting sheet  121  includes a width associated with the width of the calender nip. While an extruder and calender are capable of operating at similarly high speeds, a calender may not be as readily adjustable to changes in speed. This may affect the start-up time of system  110 , as well as the responsiveness of system  110  to restart after a temporary delay. 
         [0011]    As shown in  FIG. 3 , a roll assembly  130  may be located between sheet generator  120  and cutting assembly  140 . Roll assembly  130  generally comprises one or more rolls  132  arranged to form a translation path of sheet  121 . The take up roll described above in  FIGS. 1 and 2  may be considered as such a roll. The particular translation path directs sheet  121  to cutting assembly  140 , and may be used to tense sheet  121  as desired. The location of rolls  132  may be adjusted to impart more or less tension on sheet  121 , which may also provide a means for adjusting the cross-sectional dimensions of sheet  121 . One or more rolls  132  may be driven or powered, such as, for example, by a motor, to assist in the translation of sheet  121 , and/or adjustment of tension in sheet  121 . In addition, biasing means such as springs, pneumatic or hydraulic cylinders, etc. may force the roll against the sheet to provide tension. Sheet  121  may also be tensed by creating a speed differential between drum  125  and/or cutting drum  152 , by increasing or decreasing the rotational speed of either drum. 
         [0012]    Cutting assembly  140  generally forms strips  141  from sheet  121  for subsequent assembly of the tire band. More specifically, cutting assembly  140  utilizes a plurality of cutting members  142  to cut strips  141 , wherein each cutting member  142  includes a cutting edge  143 . Cutting members  142  generally are spaced along a length of sheet  121 , and along a circumference of cutting surface and/or cutting drum  152 . In the embodiment shown in the FIGURES, cutting members  142  are rotating knives. Rotating knives, in the embodiment shown, operate similarly to idler wheels, and freely rotate at the direction of the translating sheet  121 . Still, rotating knives  142  may be driven by a motor or any other known driving means. Also, other means for cutting sheet  121  known to one of ordinary skill in the art may be used in lieu of rotating knives, including other non-rotating knives, blades, or edges. 
         [0013]    With general reference to  FIG. 3 , system  110  also includes an applicator assembly  160  for applying one or more continuous strips  141  to a building surface to form a band. The one or more strips  141  are wound about the building surface to form the multi-layered band. Applicator assembly  160  includes an applicator drum  162  that transfers one or more strips  141  there from to building assembly  180 . To provide adhesion between applicator drum  162  and strips  141 , which promotes the separation of strips  141  from sheet  121 , applicator drum  162  may be heated or cooled. In particular embodiments, applicator drum  162  is maintained at a temperature at least 10 degrees Celsius higher than the temperature of sheet  121  and/or any strips  141 . In other embodiments, applicator drum  162  is maintained at approximately 70 degrees Celsius. The surface of applicator drum  162  may comprise a smooth surface, which may be a chromed or hot chromed surface, so to provide a smooth, capillary-like surface that may promote molecular bonding and/or may operate like a vacuum to facilitate retention of strips  141  thereon. Improved adhesion may also be provided by providing a rough surface, the rough surface providing increased surface area for improved contact area, and therefore, increased adhesion. Applicator drum  162  may also operate as the cutting drum  152 . Further, the temperature controls and conditions, as well as the surface conditions and treatments discussed with regard to applicator drum  162  above may also be applied to cutting drum  152  to improve adhesion between drum  152  and sheet  121 . Using this system, tread features can be built onto a green or uncured tire layer by layer. 
         [0014]    As just described regarding the applicator or cutting drum, the adhesion of rubber strips to a round and rotating surface is apt to occur. Accordingly, when multiple rotating surfaces are present near the exit of the nip of calender rolls, e.g. their respective circumferential surfaces that are rotating away from nip exit, a sheet of elastomeric mix can bond with either of these surfaces, or partially to both at the same time. This can be a problem during the operation of the calender, but especially during the initialization or start-up of the calender as an initial sheet needs to be directed, often by an operator, to follow the proper path until the calender has been successfully “threaded” and is ready to supply a sheet of material to the desired production center. This requires shut-down of the equipment for safety reasons, which can be costly. 
         [0015]    Looking back at  FIG. 2 , the desired path is denoted by a solid outline of material and an unwanted path by dashed arrows. As can be seen, the first unwanted path can occur when the sheet sticks to the first roll  12  where it rotates clockwise away from the exit  28   a  of the first nip  24   a.  This can lead it back to the top bank  30   a  of kneaded material, creating an undesirable feedback loop where excessive material will spill off the axial ends of the roll and down the sides of the calendering apparatus, potentially causing damage to the apparatus or other equipment by gumming up the equipment and stopping production. A similar situation can occur when the sheet exits the second nip  24   b  as it can continue to run clockwise on the second roll  14  and into the top bank of material  30   a.  After the third nip  24   c,  the material can recycle itself back to the second nip  24   b,  creating unwanted growth of a second bank  30   b  of material. Finally, after the sheet comes back around the bottom of the fourth roll  18 , it can continue to stick to this roll and create a third bank  30   c  of material near the entrance  26   c  of the third nip  24   c.    
         [0016]    Any of these banks of material can become too large and cause the equipment problems. Even after initially threading the calender, all three banks can occur due to some small residue sticking to the rolls and collecting near the entrance to the nips over time, thereby causing some small amount of recycling. Also, there is a desired amount of slight oversupply from each nip to the next that helps to ensure enough material is present for the step reduction in skim thickness at each nip which creates a full width sheet that is smooth, homogenous and that has the correct thickness. So, it is desirable to control the size of the banks of material but not to eliminate them altogether. 
         [0017]    The reason elastomeric mixes are tacky will now be explained. Suitable compositions for making a sheet for use in tire components such as treads include those rubber compositions having a glass transition temperature within a defined range, said rubber compositions being based upon a diene elastomer, a plasticizing system and a cross-linking system. The diene elastomers or rubbers that are useful for such rubber compositions are understood to be those elastomers resulting at least in part, i.e., a homopolymer or a copolymer, from diene monomers, i.e., monomers having two double carbon-carbon bonds, whether conjugated or not. 
         [0018]    In summary, typical diene elastomers include highly unsaturated diene elastomers such as polybutadienes (BR), polyisoprenes (IR), natural rubber (NR), butadiene copolymers, isoprene copolymers and mixtures of these elastomers. Such copolymers include butadiene/styrene copolymers (SBR), isoprene/butadiene copolymers (BIR), isoprene/styrene copolymers (SIR) and isoprene/butadiene/styrene copolymers (SBIR). Suitable elastomers may also include any of these elastomers being functionalized elastomers. 
         [0019]    In addition, the elastomeric composition disclosed herein may further include a reinforcing filler. Reinforcing fillers are added to, inter alia, improve the tensile strength and wear resistance of the material. Any suitable reinforcing filler may be suitable for use in compositions disclosed herein including, for example, carbon blacks and/or inorganic reinforcing fillers such as silica, with which a coupling agent is typically associated. Inorganic reinforcing fillers may take many useful forms including, for example, as powder, microbeads, granules, balls and/or any other suitable form as well as mixtures thereof. Examples of suitable inorganic reinforcing fillers include mineral fillers of the siliceous type, such as silica (SiO2), of the aluminous type, such as alumina (AlO3) or combinations thereof 
         [0020]    For coupling the inorganic reinforcing filler to the diene elastomer, a coupling agent that is at least bifunctional provides a sufficient chemical and/or physical connection between the inorganic reinforcement filler and the diene elastomer. Examples of such coupling agents include bifunctional organosilanes or polyorganosiloxanes. Such coupling agents and their use are well known in the art. The coupling agent may optionally be grafted beforehand onto the diene elastomer or onto the inorganic reinforcing filler as is known. Otherwise it may be mixed into the rubber composition in its free or non-grafted state. 
         [0021]    In addition to the diene elastomer and reinforcing filler, particular embodiments of the rubber composition disclosed herein may further include a plasticizing system. The plasticizing system may provide both an improvement to the processability of the rubber mix and/or a means for adjusting the rubber composition&#39;s glass transition temperature and/or rigidity. Suitable plasticizing systems may include a processing oil, plasticizing resin or combinations thereof. Other plasticizing systems are known. Table I below provides an example of rubber mixes that may be used with the present invention and, more particularly, indicates the percentage of resin and plasticizer that may be present and the type of resin. Other mixes may be used as well. Of resin types, limonene resin is one of the stickiest and was used in tests (discussed below) to demonstrate the efficacy of the invention. 
         [0000]    
       
         
               
               
               
               
             
               
               
               
               
             
           
               
                 TABLE I 
               
               
                   
               
               
                   
                   
                 % Total Plasticizer 
                   
               
               
                 Mix 
                 % Resin 
                 (include oil and resin) 
                 Resin Type 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 1 
                 8.7 
                 21.8 
                 Limonene 
               
               
                 2 
                 7.0 
                 7.0 
                 Formophenolic 
               
               
                   
                   
                   
                 (i.e. tackifier resin) 
               
               
                   
               
             
          
         
       
     
         [0022]    Also, the rubber compositions disclosed herein may have, or be cured with, any suitable curing system including a peroxide curing system or a sulfur curing system, many of which are known in the art. Other additives can be added to the rubber compositions disclosed herein as known in the art. Such additives may include, for example, some or all of the following: antidegradants, antioxidants, fatty acids, pigments, waxes, stearic acid and zinc oxide. 
         [0023]    These constituents, notably the polymers used in the elastomeric mix, make the sheet sticky or have tack. Increasing the amount or type of certain ingredients such as pigments, fillers, additives, and plasticizers can increase tack. Also, some polymers have inherently more tack than others. Consequently, different mixes have more tack than others and can therefore be more prone to the problems just described. 
         [0024]    As can be imagined, a number of methods have been devised to control or eliminate unwanted sticking of the sheet of material to calender rolls. Some methods have been already described above and include providing a temperature or surface finish differential between the two rolls that define a nip so that the sheet of material is prone to stick to one versus the other. Also, surface treatments that decrease adhesion to the roll to which adherence is undesirable after the sheet exits the nip can be applied to that roll. Such treatments include TEFLON, alkanolamines, alkylene glycols, and polyalkylene glycols (see U.S. Pat. No. 3,841,899). In Japanese Patent Application Publication No. JP9201838A, there is disclosed a method of continually applying a release agent on a roll using a soft roll onto which the agent is sprayed that rubs against the roll for solving sticking problems associated with that roll. Finally, the use of scraper blades is often used to prevent the unwanted recycling of material that can contribute to bank growth over time (See Jap. Pat. Application Publication No. 08-197558 A and U.S. Pat. No. 4,221,022 for examples). Also, the use of scraper blades to prevent the improper threading of a sheet processed by a calender processing elastomeric mixes, preventing it from recycling to the entrance of the nip thereby aiding in the start-up of a calendering process is also known (see col. 3, lines 5-10 of U.S. Pat. No. 4,871,409). 
         [0025]    However, all these methods have drawbacks. Concerning maintaining the temperature of the rolls, it is necessary to maintain consistency the entire time the calendering apparatus is running, which could be difficult depending on ambient conditions. Also, this method could delay start-up until the rolls reach the desired temperature. Surface treatments that are applied to rolls such as disclosed in U.S. Pat. No. 3,841,800 can wear off over time which adds cost to reapply the treatment and possibly some downtime for the equipment. Continuously applying a release agent can be both expensive and messy, and may cause the agent to seep into the material causing a degradation of the properties of the sheet of material. Finally, scraper blades do not allow for the automatic, hands-free threading of a calender processing an elastomeric mix as admitted by the prior art (see comments regarding U.S. Pat. No. 4,871,409 above). 
         [0026]    Accordingly, a method and apparatus for solving the sticking issue upon start-up in a more reliable and cost-effective way without degrading the material properties of the sheet produced by the calender would be beneficial. Such a method and apparatus that can allow for the automatic and hands-free threading of the apparatus would be particularly beneficial. Additionally, such a method and apparatus that can help maintain uninterrupted and continuous production of the calendering system after startup would also be useful. 
       SUMMARY OF THE INVENTION 
       [0027]    The present invention relates to a method and apparatus for automatic and hands-free threading of an elastomeric mix into a calender set of rolls comprising one or more pairs of rolls that have a nip between them. More specifically, a wedge is provided with a tip that is positioned downstream from the nip and at a predetermined distance from the nip. As the rolls of the nip are rotated, the tip of the edge removes all, or a desired portion of, the elastomeric mix from a first roll of the nip so as to transfer the elastomeric mix to a second roll of the nip. The tip of the wedge may be placed into contact with the first roll. The wedge may also have an arcuate surface, shaped e.g., like the outer surface of the first roll, and positioned a predetermined distance from the outer surface of the first roll. Additional objects and advantages of the invention will be set forth in part in the following description, or may be apparent from the description, or may be learned through practice of the invention. 
         [0028]    In one exemplary aspect, the present invention provides a method for operating a calendering system that processes elastomeric mixes at a desired calendering rate. The calendering system includes a first roll and a second roll that form a nip therebetween. The method includes the steps of providing a wedge with an angled tip; positioning the tip of the wedge adjacent to, and downstream of, the nip; rotating an outer surface of the first roll in a first roll surface direction at a first roll surface speed; rotating an outer surface of the second roll in a second roll surface direction at a second roll surface speed wherein the second roll surface direction is the same as the first roll surface direction; contacting an elastomeric mix with the wedge; removing all or a portion of the elastomeric mix from the outer surface of the first roll; and transferring the elastomeric mix to the outer surface of the second roll. 
         [0029]    In another exemplary embodiment, the present invention provides a calendering system for processing an elastomeric mix at a desired calendering rate. The system includes a first roll having an outer surface and rotatable along a first roll surface direction, and a second roll having an outer surface and rotatable along a second roll surface direction that is the same as the first roll surface direction. The second roll is positioned next to the first roll so as form a nip therebetween for the elastomeric mix. The nip has a centerline. A wedge is positioned downstream of, and adjacent to, the nip and at a predetermined distance D from the centerline of the nip. The wedge has a tip oriented towards the nip and configured to remove all, or a portion of, an elastomeric mix from the first roll and transfer the same to the second roll. 
         [0030]    These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0031]    A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which: 
           [0032]      FIG. 1  illustrates a perspective view of an exemplary calendering operation. 
           [0033]      FIG. 2  is a side view of the rolls of the calendering apparatus shown in  FIG. 1  with certain features removed to further reveal the position and operation of the rolls. 
           [0034]      FIG. 3  illustrates an exemplary production center that uses a calendered sheet for making strips that are applied to a green tire to create the tread of the tire. 
           [0035]      FIGS. 4-6  are side views of exemplary embodiments of the present invention. 
           [0036]      FIG. 7  is a perspective view and  FIG. 8  is a top view of an exemplary assembly for extending and retracting an exemplary wedge relative to a nip of a calendering system. 
       
    
    
       [0037]    The use of the same reference numerals in different figures denotes the same or similar features. 
       DETAILED DESCRIPTION 
       [0038]    For purposes of describing the invention, reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment, can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents. 
         [0039]      FIG. 4  provides a side view of an exemplary embodiment of the present invention in which a wedge  32  with an edge or tip  40  is provided proximate and downstream to a nip formed by the pair of rolls  16  and  18  (which will also be referred to as first roll  16  and second roll  18  for purposes of describing the operation of wedge  32 ). Rolls  16  and  18  are chosen by way of example, as a wedge and its tip could be used at any one or more of the nips provided by calendering system  10 . 
         [0040]    First roll  16  and second roll  18  rotate in opposite directions. For example, from the vantage point of  FIG. 4 , first roll  16  rotates clockwise (arrow R 16 ) while second roll  18  rotates counter-clockwise (arrow R 18 ). For purposes of the describing this exemplary embodiment of the invention, it can be understood that the outer surface  36  of first roll  16  moves in a “first roll surface direction.” The outer surface  38  of the second roll  18  moves in a “second roll surface direction,” which is the same direction as the first roll surface direction. As a result, material exiting the nip formed by first roll  16  and second roll  18  is directed towards wedge  32 . As described previously, preferably the material is transferred to second roll  18  and travels as indicated by arrow  39 . However, during e.g., start-up operations, all (or an unacceptable portion) of the elastomeric mix of material may remain undesirably on first roll  16  as indicated by dashed arrow  37 . 
         [0041]    However, for this exemplary embodiment of the invention, material continuing on first roll  16  will come into contact with the tip  40  of wedge  32 , which is positioned proximate to the nip and downstream thereof (in terms of the direction of flow of the elastomeric mix of material). As a result, all or some portion of the material will be removed from the outer surface of first roll  16  and transferred to the outer surface  38  of second roll  18  and travel as indicated by arrow  39 . Wedge  32  also has a material directing surface  44  that faces toward second roll  18  and can assist with transferring the elastomeric mix of material to second roll  18 . 
         [0042]    For this exemplary embodiment, tip  40  is in positioned in contact with the outer surface  36  of first roll  16 . Additionally, wedge  32  is forced towards first roll  16  so as to urge tip  40  against first roll  16  with a certain amount of force. For example, as shown in  FIG. 8 , first roll  16  rotates about an axis A has a width W along its axial direction. The tip  40  of wedge  32  also has a corresponding width W along the axial direction A. For this exemplary embodiment, tip  40  is contacted against the outer surface  36  of first roll  16  with a force in the range of about 2 to about 6 Newtons per millimeter of axial width W of the first roll  16 . In another exemplary embodiment, such force is about 4 Newtons per millimeter of axial width W of the first roll  16 . 
         [0043]    Tip  40  can also be provided as a relatively “sharp” tip or edge to assist in the removal of material. For example, in one embodiment of the invention, tip  40  is created with a radius of less than 1 mm. Other values may be used for the radius as well. 
         [0044]    Wedge  32  can be made from material that will reduce the possibility of damaging the outer surface  36  of first roll  16 . For example, wedge  32  can be made from a material such as e.g., brass that is “softer” than the material used for first roll  16 . Alternatively, or in addition thereto, wedge  32  may treated with a coating or surface treatment that reduces the ability of the elastomeric mix material to stick or adhere to wedge  32 . By way of example, wedge  32  may be constructed of a hardened steel to which a coating of Teflon® or other non-stick material has been applied. For example, the coating may be applied to tip  40 , material directing surface  44 , or both. 
         [0045]    Referring again to  FIG. 4 , the nip created by first roll  16  and second roll  18  defines a centerline designated as C/L in  FIG. 4 . More particularly, centerline C/L is defined as a line that is centered in the nip between outer surfaces  36  and  38  and is perpendicular to a line passing through the axis of rotation of both first roll  16  and second roll  18 . As shown, tip  40  is positioned at a predetermined distance D from centerline C/L as measured along a direction orthogonal to centerline C/L. In one exemplary embodiment of the invention, predetermined distance D is in the range of e.g., about 5 mm to about 15 mm. 
         [0046]    Table II below provides experimental results of at least 14 trials conducted with elastomeric mixes 1 and 2 from Table 1 and a wedge  32  constructed and positioned according to the exemplary embodiment of  FIG. 4 . The surface speeds of first roll  16  and second roll  18  were varied relative to each other. A constant pressure was applied to first roll  16  using wedge  32 . 
         [0000]    
       
         
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE II 
               
               
                   
               
               
                   
                   
                   
                 First Roll/ 
                   
                   
                   
                   
               
               
                   
                   
                   
                 Second 
                   
                 Actu- 
               
               
                   
                   
                 First 
                 Roll 
                 Second 
                 ators 
                 Skim 
                   
               
               
                   
                 Trial 
                 Roll 16 
                 Speed 
                 Roll 18 
                 pressure 
                 Thickness 
                 OK/ 
               
               
                 Mix 
                 # 
                 Speed 
                 Ratio 
                 Speed 
                 (bar) 
                 (mm) 
                 NOK 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 1 
                 1 
                 5.75 
                 115% 
                 5.0 
                 6 
                 0.9 
                 OK 
               
               
                   
                 2 
                 5.75 
                 115% 
                 5.0 
                 6 
                 0.9 
                 OK 
               
               
                   
                 3 
                 5.75 
                 115% 
                 5.0 
                 6 
                 0.9 
                 OK 
               
               
                   
                 4 
                 5.75 
                 115% 
                 5.0 
                 6 
                 0.9 
                 OK 
               
               
                   
                 5 
                 5.75 
                 115% 
                 5.0 
                 6 
                 0.9 
                 OK 
               
               
                   
                 6 
                 4.25 
                 85% 
                 5.0 
                 6 
                 0.9 
                 OK 
               
               
                   
                 7 
                 5.75 
                 115% 
                 5.0 
                 6 
                 0.9 
                 OK 
               
               
                   
                 8 
                 11.50 
                 115% 
                 10.0 
                 6 
                 0.9 
                 OK 
               
               
                   
                 9 
                 11.50 
                 115% 
                 10.0 
                 6 
                 0.9 
                 OK 
               
               
                 2 
                 10 
                 5.75 
                 115% 
                 5.0 
                 6 
                 0.9 
                 OK 
               
               
                   
                 11 
                 5.75 
                 115% 
                 5.0 
                 6 
                 0.9 
                 OK 
               
               
                   
                 12 
                 4.25 
                 85% 
                 5.0 
                 6 
                 0.9 
                 OK 
               
               
                   
                 13 
                 8.5 
                 85% 
                 10.0 
                 6 
                 0.9 
                 OK 
               
               
                   
                 14 
                 11.5 
                 115% 
                 10.0 
                 6 
                 0.9 
                 OK 
               
               
                   
               
             
          
         
       
     
         [0047]    In Table II, the skim thickness refers to the thickness of the elastomeric mix travelling on the rolls. “OK” indicates that all or an acceptable portion of the material transferred from the first roll to the second roll after removal by the wedge while NOK indicates no transfer or an unacceptable amount of transfer. As indicated by Table II, the surface speeds of the rolls forming the nip did not affect the ability of wedge  32  to properly remove elastomeric mix from the first roll  16  so that the material could transfer to second roll  18 . 
         [0048]      FIG. 5  provides another exemplary embodiment of wedge  32  positioned in the nip created by first roll  16  and second roll  18 . This exemplary embodiment is similar to the exemplary embodiment of  FIG. 4  except that wedge  32  has a different shape and is provided with an arcuate surface  42  that, along with tip  40 , is placed in contact with the outer surface  36  of first roll  16 . As with previous embodiments, wedge  32  is positioned adjacent and downstream of the nip and at a predetermined distance D from the centerline of the nip. 
         [0049]      FIG. 6  provides another exemplary embodiment of wedge  32  positioned in the nip created by first roll  16  and second roll  18 . This exemplary embodiment is also similar to the exemplary embodiment of  FIG. 4  except that wedge  32  has a different shape and is provided with an arcuate surface  42 . Additionally, unlike the embodiment of  FIG. 4 , tip  40  and arcuate surface  42  are not placed in contact with the outer surface  36  of first roll  16 . Instead, a predetermined distance S is maintained between arcuate surface  42  and outer surface  36 . S is measured along the radial direction of first roll  16  and is measured as the distance between outer surface  36  and the closest point on arcuate surface  42 . Arcuate surface  42  is also constructed with the same radius of curvature as the outer surface  36  of first roll  16 . Wedge  32  has a material directing surface  44  that is also arcuate so as to help further direct material towards second roll  18  after removal from first roll  16 . As with previous embodiments, wedge  32  is positioned adjacent and downstream of the nip and at a predetermined distance D from the centerline of the nip. 
         [0050]    Table IV below provides experimental results of at least 10 trials conducted with different thickness of elastomeric mix 1 from Table 1 and a wedge  32  constructed and positioned according to the exemplary embodiment of  FIG. 6 . The surface speeds of first roll  16  and second roll  18  were varied relative to each other as well as the predetermined distance S. 
         [0000]    
       
         
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE IV 
               
               
                   
               
               
                   
                   
                   
                 First 
                   
                   
                   
                   
               
               
                   
                   
                   
                 Roll/ 
               
               
                   
                   
                   
                 Second 
               
               
                   
                   
                 First 
                 Roll 
                 Second 
                 Distance 
                 Skim 
               
               
                   
                 Trial 
                 Roll 16 
                 Speed 
                 Roll 18 
                 S 
                 Thickness 
                 OK/ 
               
               
                 Mix 
                 # 
                 Speed 
                 Ratio 
                 Speed 
                 (mm) 
                 (mm) 
                 NOK 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 1 
                 1 
                 3.2 
                 156% 
                 5 
                 0.25 
                 0.8 
                 NOK 
               
               
                   
                 2 
                 3.2 
                 156% 
                 5 
                 0.25 
                 0.8 
                 NOK 
               
               
                   
                 3 
                 3.2 
                 156% 
                 5 
                 0.25 
                 0.8 
                 NOK 
               
               
                   
                 4 
                 3.2 
                 156% 
                 5 
                 0 
                 0.8 
                 OK 
               
               
                   
                 5 
                 3.2 
                 83% 
                 5 
                 0 
                 1.0 
                 OK 
               
               
                   
                 6 
                 6 
                 83% 
                 5 
                 0 
                 1.0 
                 OK 
               
               
                   
                 7 
                 6 
                 80% 
                 5 
                 0 
                 1.0 
                 OK 
               
               
                   
                 8 
                 50 
                 80% 
                 40 
                 0 
                 1.0 
                 OK 
               
               
                   
                 9 
                 75 
                 80% 
                 60 
                 0 
                 1.0 
                 OK 
               
               
                   
                 10 
                 100 
                 80% 
                 80 
                 0 
                 1.0 
                 OK 
               
               
                   
               
             
          
         
       
     
         [0051]    As indicated by Table IV, the surface speeds of the rolls forming the nip did not affect the ability of wedge  32  to properly remove elastomeric mix from the first roll  16  so that the material could transfer to second roll  18 . Contact between wedge  32  and first roll  16  was required in order to successfully remove and transfer the desired amount of elastomeric mix material. However, the inventor believes this is the result of imperfections in the shape of the arcuate surface  42  of wedge  32  used for the trials and that a surface  32  more closely matched to the shape of first roll  16  will work. For example, it is believed that using a precision ground surface  32  will likely work but will be more expensive. 
         [0052]    A wedge can be similarly positioned downstream and adjacent to each the nips created by the rolls  12 ,  14 ,  16 ,  18 , and  20  (or any combination thereof) to ensure that the elastomeric mix material is properly routed after exiting each nip. For example, a wedge could be configured with a first roll  12  and second roll  14  and/or first roll  14  and second roll  16 , and so on. Also, the wedge can be left in position after start-up and during the calendering process or could be withdrawn after start-up. 
         [0053]    For example,  FIGS. 7 and 8  illustrate a retractable mounting mechanism for positioning the tip  40  of wedge  32  into contact with a first roll  16 . A pair of pneumatic or hydraulic actuators  48  and  50  are mechanically connected with a pair of slide assemblies  44  and  48  that carry wedge  32 . The slide assemblies contain rollers or bearings that allow the slides to readily extend wedge  32  into contact with first roll  16  and retract wedge  32  from roll  16  under the power of actuators  48  and  50 . Accordingly, calendering system  10  can be provided with e.g., a processing device or controller to extend wedge  32  into contact with first roller  16  during start-up and maintain its position until the elastomeric mix material has been properly threaded. Wedge  32  can then be retracted or allowed to remain in place if desired. 
         [0054]    While the present subject matter has been described in detail with respect to specific exemplary embodiments and methods thereof, it will be appreciated that those skilled in the art, upon attaining an understanding of the foregoing may readily produce alterations to, variations of, and equivalents to such embodiments. Accordingly, the scope of the present disclosure is by way of example rather than by way of limitation, and the subject disclosure does not preclude inclusion of such modifications, variations and/or additions to the present subject matter as would be readily apparent to one of ordinary skill in the art using the teachings disclosed herein.