Abstract:
A system is provided for placement of noise attenuating foam along an inside surface of a tire to attenuate cavity noise. The system can be used with tires of various sizes and shapes such that different foam sizes may be utilized. The system provides for automating the process of foam placement in a manner that allows for consistent placement of the foam during e.g., tire manufacture.

Description:
FIELD OF THE INVENTION 
       [0001]    The subject matter of the present disclosure relates generally to the placement of a ring into a tire cavity against an interior surface of the tire. 
       BACKGROUND OF THE INVENTION 
       [0002]    Noise emitted by a tire rolling across a road surface is attributable mainly to the vibrations of the contacting surface of the tire with road surface irregularities that generate various acoustic waves. At least a portion of these acoustic waves can be perceived by the human ear as noise both inside and outside of the vehicle. The amplitude of the noise is dependent on e.g., vibration modes of the tire and also the nature of the road surface on which the vehicle moves. The frequency range corresponding to the noise generated by the tire typically ranges from about 20 Hz to 4000 Hz. 
         [0003]    Noise outside the vehicle can be attributed to various interactions between e.g., the tire and the road surface and the tire and the air, each of which can cause discomfort to persons along the moving vehicle. The sources of such noise include the impact of the roughness of the road with the contact area of the tire as well as noise generated due to the arrangement of the elements of the tread and its resonance along different paths. The frequency range for such noise can range from about 300 Hz to about 3000 Hz. 
         [0004]    Regarding the noise heard inside the vehicle, the modes of sound propagation include vibrations transmitted through the wheel center and the suspension system (up to about 400 Hz) as well as vibrations from aerial transmission of acoustic waves, which can include the high frequency spectrum (about 600 Hz and over). 
         [0005]    One important contribution to the noise heard inside the vehicle is provided by cavity noise, which refers to the discomfort caused by the resonance of the air within the tire cavity. This cavity noise is predominant in a specific frequency spectrum between 200 Hz and 250 Hz depending on the geometry of the tire. 
         [0006]    To reduce the rolling noise of a tire, particularly cavity noise, it is known to provide the inner wall of the tire with a layer of foam such as e.g., a foam as described in patents or patent applications WO 2006/117944 or U.S. Pat. No. 7,975,740, WO 2007/058311 and U.S. 2009/0053492, U.S. 2007/0175559, WO 2008/062673 and U.S. 2010/0038005, U.S. 2009/0053492, WO 2010/000789 and U.S. 2011/0308677, EP 1529665 or U.S. Pat. No. 7,182,114. 
         [0007]    Challenges exist with development of processes and equipment for repeatedly locating the foam in the tire cavity and along the interior surface or wall. For example, tires are currently produced in a wide range of sizes and shapes requiring either different placement machines or adjustability of such machines. Also, if the foam is to be placed by insertion in the tire cavity against the inner surface of the tire in the crown portion, navigation past the tire seat must be considered. The tire seat has a smaller diameter relative to the diameter of the inner surface of the tire. Other challenges also exist. 
         [0008]    Accordingly, a system for positioning noise attenuating foam inside a tire against the interior surface would be useful. Such a system that can consistently position the foam over a range of different tires sizes and shapes would be beneficial. Such a system that can be automated would also be particularly useful. 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention provides a system for placement of noise attenuating foam along an inside surface of a tire to attenuate cavity noise. The system can be used with tires of various sizes and shapes such that different foam sizes may be utilized. The system provides for automating the process of foam placement in a manner that allows for consistent placement of the foam during e.g., tire manufacture. 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. 
         [0010]    In one exemplary embodiment of the present invention, a device for placement of a ring onto an interior surface of a tire is provided. The device defines a central axis. The device includes a plurality of holders arranged around the central axis and configured for selectively holding and releasing the ring. A plurality of telescoping arm assemblies are arranged around the central axis, each arm assembly supporting at least one of the holders. Each arm assembly is configured for selectively extending and retracting the holder along a radial direction that is orthogonal to the central axis. A positioning plate is rotatable about the central axis and includes a plurality of guides extending from the central axis along the radial direction. Each guide is in receipt of at least one telescoping arm assembly and is configured so that rotation of the positioning plate about the central axis causes the telescoping arm assemblies to move along the guides and outwardly or inwardly along the radial direction depending upon the direction of rotation of the positioning plate. 
         [0011]    In another exemplary aspect, the present invention provides a method for placement of a ring onto an interior surface of a cavity of a tire. The ring has an outside diameter and defines radial and circumferential directions. The method includes the steps of contracting the ring along the radial direction from a first shape to a smaller, second shape, wherein second shape comprises a plurality of folds of the ring along the circumferential direction; placing the ring while in the second shape into the tire cavity; expanding the ring to the first shape and within the tire cavity so as to remove the plurality of folds of the ring along the circumferential direction; and positioning a radially-outermost surface of the ring against the interior surface of the tire. 
         [0012]    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 
         [0013]    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: 
           [0014]      FIG. 1  is a schematic representation of certain steps in an exemplary method of the present invention. In  FIG. 1 , the sidewall of an exemplary tire is not shown for purposes of additional clarity in explaining this exemplary method. 
           [0015]      FIG. 2  is an elevation view of an exemplary embodiment of the present invention. 
           [0016]      FIG. 3  is a top view of the exemplary embodiment of  FIG. 2  supporting an exemplary foam ring. 
           [0017]      FIG. 4  is a bottom view of the exemplary embodiment of  FIG. 2 . 
           [0018]      FIG. 5  provides a perspective view of a partial cross-section of the exemplary embodiment of  FIG. 2 . 
           [0019]      FIG. 6  is a partial side view of an exemplary telescoping arm assembly in a retracted position. 
           [0020]      FIG. 7  is another partial side view of the exemplary telescoping arm assembly of  FIG. 6  in an extended position so as to place the exemplary foam ring against the inside surface of a tire. 
           [0021]      FIG. 8  is a perspective view of an exemplary holder of the present invention. 
           [0022]      FIG. 9  is an end view of the exemplary holder of  FIG. 8  before gripping an exemplary foam ring. 
           [0023]      FIG. 10  is another end view as in  FIG. 9  of the exemplary holder while gripping the foam ring. 
           [0024]      FIG. 11  is another elevation view of the exemplary embodiment of  FIG. 2  with the foam ring elevated into position for insertion into a tire cavity. 
           [0025]      FIG. 12  is another top view of the exemplary embodiment of  FIG. 2  supporting the exemplary foam ring in an exemplary first shape. 
           [0026]      FIG. 13  is another top view of the exemplary embodiment of  FIG. 2  supporting the foam ring in an exemplary second shape. 
           [0027]      FIG. 14  is another elevation view of the exemplary embodiment of  FIG. 2  with the foam ring supported by exemplary holders and a ring support plate in a lowered position. 
           [0028]      FIG. 15  is another elevation view of the exemplary embodiment of  FIG. 2  with an exemplary tire before insertion of the foam ring. 
           [0029]      FIG. 16  is another elevation view of the exemplary embodiment of  FIG. 2  illustrating positioning of the foam ring into the tire cavity against the interior surface with telescoping arm assemblies shown in an extended position. 
           [0030]      FIG. 17  repeats the elevation view of  FIG. 11  with telescoping arm assemblies shown in a retracted position. 
       
    
    
     DETAILED DESCRIPTION 
       [0031]    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 
         [0032]      FIG. 1  provides a schematic representation of an exemplary method of the present invention as illustrated in steps  1 A through  1 D. In step  1 A, an exemplary foam ring  50  is provided for insertion in the cavity  46  of a tire  40  for purposes of noise attenuation. Foam ring  50  is shown in a first shape, which corresponds to its original, uncontracted state before insertion into tire  40 . Foam ring  50  defines a radial direction R and a circumferential direction C. 
         [0033]    In this first shape, ring  50  has an outside diameter D 1  that exceeds the inner seat diameter D 3  of the seat  44  of tire  40 . By way of example, foam ring  50  may comprise a polyurethane foam as described in WO/2013/182477, but other materials may also be used. Similarly, the shape and dimensions of ring  50  shown in  FIG. 1  and other figures herein are provided by way of example only as other constructions may be used as well. In step  1 A, an adhesive may be applied to the radially-outermost surface  60  of foam ring  50  for purposes of adhering foam ring  50  to interior surface  42  (e.g., the inner liner) of tire  40 . Alternatively, the adhesive may have previously been applied to the interior surface  42  of the tire  40  for the same purposes. 
         [0034]    In step  1 B, foam ring  50  is contracted along radial direction R from the first shape shown in step  1 A to a smaller, second shape. In this second shape, foam ring  50  forms a plurality of outward opening folds  52  and inward opening folds  54  in an alternating manner along circumferential direction C (also shown e.g., in  FIG. 13 ). For this exemplary embodiment, the folds are U-shaped and provide a “daisy” configuration with a contracted diameter D 2  as depicted in step  1 B. Contracted diameter D 2  is less than the original outside diameter D 1  and is also less than seat diameter D 3 . In one exemplary aspect of the present invention, the contracted, second shape shown in step  1 B is created by pulling foam ring  50  radially inward at multiple points  56  along circumferential direction C so as to form folds  52  and  54 . 
         [0035]    As shown in step  1 C, foam ring  50  is next inserted through the seat  44  of tire  40  and into tire cavity  46 . Because contracted diameter D 2  is less than seat diameter D 3 , foam ring  50  may be readily placed into tire cavity  46 . The folded or contracted configuration used for the second shape of foam ring  50  allows the present invention to be used with a variety of different tire shapes and sizes. 
         [0036]    In step  1 D of  FIG. 1 , foam ring  50  is expanded back to the first shape. This step may performed by moving the foam ring  50  radially outward at multiple points  56  along circumferential direction C so as to remove the plurality of folds  52  and  54 . The inherent resiliency of the foam ring  50  may be sufficient to restore foam ring  50  back to its first shape during the expanding step  1 D. Notably, it should be understood that foam ring  50  may not be returned completely to original diameter D 1  upon expansion and placement against interior surface  42  and such is not necessarily required. 
         [0037]    As foam ring  50  is expanded, its radially-outermost surface  60  is eventually placed into contact with the interior surface  42  of tire  40  along its crown portion. If an adhesive has been applied to radially-outermost surface  60 , such contact will allow foam ring  50  to be adhered to the interior surface  42  of tire  40 . Once foam ring  50  is secured to interior surface  42 , tire  40  can be e.g., mounted onto a wheel of a vehicle to provide noise attenuation during operation of the vehicle. 
         [0038]    A side view of an exemplary foam ring placement device  100  is shown in  FIG. 2  while a top view is shown in  FIG. 3 . Device  100  defines a central axis CA ( FIG. 2 ) along its centerline and a radial direction R ( FIG. 3 ) that is orthogonal to central axis CA. For this exemplary embodiment, central axis CA is shown parallel to vertical direction V. A plurality of holders  102  are positioned adjacent to each other along circumferential direction C around central axis CA. Holders  102  are configured for selectively holding and releasing foam ring  50  as will be further described. While eight holders  102  are shown for this embodiment, it should be understood that in other embodiments a different number of holders  102  may be employed. 
         [0039]    A plurality of telescoping arm assemblies  104  are also arranged around central axis CA. Each telescoping arm assembly  104  supports at least one holder  102  and is configured for selectively extending and retracting holder  102  along radial direction R. Stated differently, telescoping arm assemblies can move holders inwardly and outwardly relative to central axis CA along radial direction R. In  FIG. 2 , holders  102  are shown in an extended position while in  FIG. 3  holders  102  are shown in a retracted position. Additional details of telescoping arm assemblies  104  will be further described. 
         [0040]      FIG. 3  also depicts an exemplary foam ring  50  that has been placed onto a ring support plate  112 . Various mechanisms (not shown) can be used to raise or lower (arrows U and D in  FIG. 2 ) ring support plate  112  along central axis CA. Ring support plate  112  includes a plurality of slots  114  positioned about the circumferential direction C for providing clearance of other elements of ring placement device  100 . The size of ring support plate  112  allows for foam rings  50  of various diameters D 1  to be supported during operation of device  100 . 
         [0041]    Each telescoping arm assembly  104  includes a post  106  that extends vertically upward from a positioning plate  110  and a fixed plate  116 . Positioning plate  110  is rotatable about central axis CA relative to fixed plate  116  and is used to move each post  106  outwardly or inwardly along radial direction R depending upon the direction of rotation of plate  110 . One or more mechanisms (not shown) can be used for rotating position plate  110  during operation of device  100 . 
         [0042]      FIG. 4  provides a bottom view (along the direction of arrows  4 - 4  in  FIG. 2 ) of positioning plate  110 .  FIG. 5  provides a perspective view of cross-section of plates  110 ,  112 , and  116  along with a single telescoping arm assembly  104  for purposes of additional clarity in describing this exemplary device  100  of the invention. Each post  106  of a telescoping arm assembly  104  is attached with a support base  128 , which is connected with a boss  122 . Boss  122  is received into a linear slot  120  (defined by fixed plate  116 ) that extends along radial direction R. Boss  122  is freely movable within linear slot  120  such that telescoping arm assembly  104  can move inwardly or outwardly along radial direction R. 
         [0043]    An axle  126  extends through support base  128  and supports a roller  124  that is freely rotatable about axle  126 . Roller  124  is received into a guide  118  that, for this exemplary embodiment, is configured as a spiral slot  118  that spirals outwardly along radial direction R from central axis CA. As best seen in  FIG. 4 , a plurality of such spiral slots  118  are defined by positioning plate  110  and are positioned adjacent to one another with each slot  118  receiving a roller  124  of one of the telescoping arm assemblies  104 . 
         [0044]    The rotation of positioning plate about central axis CA and the reaction forces of rollers  124  in spiral slots  118  and bosses  122  in linear slots  120  causes movement of each telescoping arm assembly  104  outwardly or inwardly along radial direction R depending upon the direction of rotation. For example, rotation in the direction of arrow O ( FIG. 4 ) causes the telescoping arm assemblies  104  to move away from central axis CA (and each other) or outwardly along radial direction R. Conversely, rotation in the direction of arrow I ( FIG. 4 ) causes the telescoping arm assemblies  104  to move towards central axis CA (and each other) or inwardly along radial direction R. As such, positioning plate  110  can be used to selectively position telescoping arm assemblies relative to foam ring  50  on ring support plate  112 . 
         [0045]      FIG. 6  provides a close-up and partial side view of telescoping arm assembly  104  in a retracted view.  FIG. 7  provides the same view with telescoping arm assembly  104  in an extended position with a holder  102  placing foam ring  50  against the interior surface  42  along the crown portion  48  of tire  40 . Holder  102  is connected with post  106  by a plurality of links  146 ,  148 ,  150 , and  152  that pivot relative to post  106  as holder  102  is extended or retracted along radial direction R. 
         [0046]    More particularly, a pair of slidable links  146 ,  148  are pivotally connected at one end by pivot points P 1  to holder  102 , and at another end by pivot points P 3  to post  106 . Pivot points P 3  are able to move or slide up or down post  106  along vertical direction V. A motor  108  ( FIG. 2 ), such as e.g., a solenoid or pneumatic cylinder, is used to selectively control the position of pivots points P 3  by extension or retraction of shaft  130 . 
         [0047]    Slidable links  146  and  148  are pivotally connected at pivot points P 2  to fixed links  150  and  152 , which are in turn pivotally connected along an opposite end at pivot points P 4  to post  106 . The position of pivot points P 4  is fixed relative to post  106 . For this embodiment, pivot points P 2  are located at about a midpoint along the length of slidable links  146  and  148 . 
         [0048]    As shaft  130  is extended downwardly (arrow D in  FIG. 6 ), pivot points P 3  slide downwardly. However, a reaction force provided by fixed links  150  and  152  causes slidable links  146  and  148  to pivot outwardly along radial direction R thereby extending holder  102  along radial direction R away from central axis CA. Conversely, as shaft  130  is withdrawn upwardly (arrow U in  FIG. 7 ), pivot points P 3  slide upwardly and slidable links  146  and  148  pivot inwardly along radial direction R—thereby withdrawing holder  102  along radial direction R and retracting holder  102  towards central axis CA. 
         [0049]      FIG. 8  provides a perspective view of an exemplary holder  102  while  FIGS. 9 and 10  provide end views of such holder  102 . As shown, holder  102  includes a receptacle  134  with a cover  132  providing a foam ring contact surface  136 . A plurality of slots  140  are defined by contact surface  136 . Slots  140  extend laterally over contact surface  136  and are arranged parallel to each other along the longitudinal direction L of holder  102 . A plurality of pins  142 ,  144  are extendable through slots  140 . More particularly, pins  142  are provided in a row along one side of contact surface  136  while pins  144  are provided in a row along the other side of contact surface  136 . Pins  142  and  144  are disposed in an alternating manner along slots  140 . 
         [0050]    Holders  102  are employed to grasp or hold foam ring  50  during its contracting, expanding, and positioning in tire  40 . In one exemplary method, as depicted in  FIG. 9 , contact surface  136  is positioned against the radially-innermost surface  58  of foam ring  50 . Pins  142  and  144  can be extended (arrows I) through slots  140  to project into foam ring  50  and thereby secure its position onto contact surface  136  of holder  102 . Once foam ring  50  is positioned against the interior surface  42  of tire  40 , pins  142  and  144  can be retracted so as to release foam ring  50  from holder  102 . 
         [0051]    An exemplary method of using foam ring placement device  100  to position foam ring  50  will now be described with reference to the various figures. It should be understood that the steps set forth herein, including their sequence, is provided by way of example and other steps and/or sequences may be employed as well. Beginning with  FIGS. 3 and 11 , foam ring  50  is placed onto ring support plate  112 . For this starting operation, holders  102  are fully retracted along radial direction R against posts  106  ( FIG. 2 ). Posts  106  are also at their radially-innermost position nearest central axis CA ( FIG. 2 ) with rollers  125  at their radially-innermost position along guides  118  ( FIG. 4 ). 
         [0052]    Next, ring support plate  112  is moved (arrows U in  FIG. 11 ) relative to central axis CA so as to position foam ring  50  at the same height along the vertical direction as holders  102 . In  FIG. 11 , foam ring  50  is shown in its original, first shape with diameter D 1  as previously described in step  1 A of  FIG. 1 . 
         [0053]    Referring primarily to  FIG. 12 , positioning plate  110  is rotated (direction O in  FIG. 4 ) so as to cause rollers  124  of the telescoping arm assemblies  104  to track along guides  118  and move the assemblies  104  radially outward (arrow O). Rotation of positioning plate  110  is continued until each holder&#39;s contact surface  136  is placed in contact with (or in close proximity) to the radially innermost surface  58  of foam ring  50 . In the event foam ring  50  has been placed on ring support plate  112  in a non-concentric manner relative to central axis CA, the radially-outward movement of telescoping arm assemblies  104  within slots  114  of ring support plate  112  will advantageously center foam ring  50 . Additionally, because of the range of movement available for telescoping arm assemblies  104  relative to positioning plate  110 , foam rings  50  of various diameters D 1  ( FIG. 1 ) can be positioned using device  100 . Once holders  102  have been positioned as just described, pins  142  and  144  are deployed into foam ring  50  as previously described with reference to  FIGS. 9 and 10 . 
         [0054]    Next, in order to provide foam ring  50  with an overall diameter D 2  less than the seat diameter D 3  of tire  40 , positioning plate  110  is rotated (arrow I in  FIG. 4 ) in a manner that causes telescoping arm assemblies to move radially inward towards central axis CA. As illustrated in  FIG. 13 , this movement pulls foam ring  50  at multiple points  56  along circumferential direction C to provide a contracted or second shape having a plurality of folds  52  and  54  in a manner as previously described with reference to step  1 B in  FIG. 1 . 
         [0055]    As shown in  FIG. 14 , ring support plate  112  is lowered (arrows D) in preparation for placement of tire  40 . Foam ring  50  remains fixed in position by holders  102 , and also remains in its second shape. 
         [0056]    Referring now to  FIG. 15 , tire  40  is now positioned with its center TC along central axis CA and above device  100 . Tire  40  is lowered (arrow D) until along vertical direction V until its center TC coincides with the center RC of foam ring  50  as depicted in  FIG. 16 . Because the overall diameter D 2  of foam ring  50  is less than the seat diameter D 3  of tire  40 , foam ring  50  can be readily placed within tire cavity  46  as previously described with reference to step  1 C in  FIG. 1 . 
         [0057]    Referring now to  FIG. 16 , motors  108  on telescoping arm assemblies  104  are deployed to move shafts  130  downward (arrows D) and thereby cause holders  102  to extend outwardly along radial direction R. Additionally, positioning plate  110  is again rotated (arrow O in  FIG. 4 ) in a manner that causes telescoping arm assemblies  104  to move outward along the radial direction R so as to move foam ring  50  toward tire  40  until the radially-outermost surface of foam ring  50  is positioned against the interior surface  42  of tire  40  along crown portion  48 . As previously stated, the use of adhesive allows foam ring  50  to be adhered to tire  40 . Ability to positioning holders  102  over a wide range along radial direction R allows tire of different shapes and sizes to be equipped with a foam ring. 
         [0058]    Once ring  50  is installed, positioning plate  110  is rotated (arrow I in  FIG. 4 ) so as to move telescoping arm assemblies  104  towards each other and central axis CA. Motor  108  is now activated to cause shafts  130  to return as shown by arrows U in  FIG. 17 , which also retracts holders  102  along radial direction R away from tire  40  and towards central axis CA. Tire  40  with installed support ring  50  can now be lifted from the machine  100  along central axis CA and the process repeated for another tire and ring. 
         [0059]    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.