Patent Publication Number: US-9402462-B1

Title: Oral-care implement having spring-loaded cleaning elements

Description:
FIELD OF THE INVENTION 
     The present disclosure is directed to an oral-care implement, such as a toothbrush, having a plurality of cleaning elements that are spring-loaded inside the toothbrush&#39;s body. 
     BACKGROUND OF THE INVENTION 
     Recent advancements in oral-care implements include toothbrushes having angled, multi-level, and pivoting cleaning elements, such as bristles and tufts. For example, a commonly assigned U.S. Pat. No. 8,239,995 is directed to an oral-hygiene device that includes a head having a fixed component and a movable component, the latter being movable between a first configuration and a second configuration. A first bristle field extends from the fixed component, and a second bristle field extends from the movable component. The first bristle field and second bristle field are controllably movable between a first configuration for providing a first cleaning operation and a second configuration for providing a second cleaning operation. 
     A commonly assigned US Patent Application Serial No. 2002/0138926 A1 is directed to a head for an electric toothbrush including a support member having a plurality of holes, through which a plurality of bristle tufts extend. The tufts are prevented from being withdrawn from the holes when a tensile force is applied to the tufts&#39; first ends along the tufts&#39; longitudinal axes. A resilient cushion is positioned adjacent to a second side of the support member such that the tufts&#39; second ends can contact the cushion. When a compressive force is applied to the first ends of the tufts, along the long axis of each tuft, each tuft can move in its hole in a first direction into the cushion. When the compressive force is removed the cushion causes each tuft to move in its hole in a second direction substantially opposite to the first direction. Such action assists in preventing potential damage to a user&#39;s gums when excessive pressure is used during brushing of the teeth. 
     In addition to providing a cushioned mechanism to avoid a possible excessive force during brushing, one could benefit from causing the bristle tufts to move, under brushing pressure, in a desired manner, including a pattern or patterns of the bristles&#39; deflection and their angled orientation. 
     SUMMARY OF THE INVENTION 
     An oral-care implement comprises a bristle carrier and a plurality of cleaning elements embedded in and outwardly extending from the bristle-carrier. The cleaning elements can extend from the bristle carrier at different angles. 
     At least one of the plurality of cleaning elements is a spring-loaded cleaning element movably disposed in a channel formed in the bristle carrier. The spring-loaded cleaning element comprises a spring portion disposed in the channel and a projecting portion longitudinally adjacent to the spring portion. The projecting portion outwardly extends from the channel at an angle of projection relative to the longitudinal axis. 
     The spring portion is structured and configured to elastically deform inside the channel to at least partially conform to a shape of the channel. This causes the projecting portion to change its length and the angle of projection. The elastic deformation of the spring portion inside the channel can be designed to progress in accordance with a predetermined pattern based, at least partially, on the shape of the channel. 
     The channel comprises a curved portion structured and configured to facilitate the elastic deformation of the spring portion of the spring-loaded cleaning element inside the channel. In one embodiment, the channel includes a closed end and an open mouth opposite to the closed end, wherein the closed end supports an embedded end of the spring portion disposed in the channel, and the open mouth facilitates a movement of the spring-loaded cleaning element therethrough when the spring portion elastically deforms inside the channel. The movement of the spring-loaded cleaning element through the open mouth of the channel may include a change of the angle of projection of the projecting portion of the spring-loaded cleaning element. 
     In one embodiment, the oral-care implement comprises a shaft connected to the spring-loaded cleaning element. The shaft can be structured and configured to travel inside a channel along a travel path. 
     In one embodiment, an oral-care implement comprises a plurality of spring-loaded cleaning elements embedded in and outwardly extending from the bristle-carrier. Each of the spring-loaded cleaning elements is disposed in its respective channel formed in the bristle carrier and outwardly extends from the channel through an open mouth thereof. Each of the spring-loaded cleaning elements can be structured and configured to elastically deform inside the channel, wherein angles of projection at which individual spring-loaded cleaning elements outwardly extend from the bristle carrier change as the spring-loaded cleaning elements elastically deform inside their respective channels. 
     In a further embodiment, at least some of the angles of projection at which the individual spring-loaded cleaning elements outwardly extend from the bristle carrier differ from one another. In another embodiment, the angles of projection at which the individual spring-loaded cleaning elements outwardly extend from the bristle carrier may change non-uniformly relative to one another. 
     In one embodiment, each of the spring-loaded cleaning elements comprises a spring portion and a projecting portion longitudinally adjacent to the spring portion, wherein the spring portion is disposed in the channel and the projecting portion outwardly extends from said channel through an open mouth of the channel. The spring portion terminates with an embedded end thereof disposed in the channel. The projecting portion terminates with a free end. The spring portion is structured to elastically deform inside the channel when the oral-care implement is in use. This elastic deformation causes the second portion to change its length and the angle of projection. 
     In one embodiment, each of the channels includes a travel path disposed therein to receive a shaft for movement along the travel path. The shaft can be connected to the spring-loaded cleaning element, i.e., intermediate its embedded end and its free end. In use, a movement of the shaft along the travel path facilitates elastic deformation of the spring-loaded cleaning element inside the channel according to a predetermined pattern. 
     In a further embodiment, the oral-care implement may comprise channels having differential shapes—to cause differential elastic deformation of the spring-loaded cleaning elements. For example, the oral-care implement may comprise at least a first channel and a second channel, the first channel having a first spring-loaded cleaning element therein and the second channel having a second spring-loaded cleaning element therein, wherein a shape of the first channel is different from a shape of the second channel. In such an embodiment, the first channel can be configured to facilitate a first elastic deformation of the first spring-loaded cleaning element, and the second channel can be configured to facilitate a second elastic deformation of the second spring-loaded cleaning element, the first elastic deformation being different from the second elastic deformation. This results in the change of the angle of projection of the first spring-loaded cleaning element being different from the change of the angle of projection of the second spring-loaded cleaning element. 
     In a further embodiment, the first spring-loaded cleaning element may differ from the second spring-loaded cleaning element in at least one physical characteristic selected from the group consisting of length, thickness, geometry including, e.g., cross-sectional shape and area moment of inertia, stiffness, elasticity, surface energy, chemical composition, color, and any combination thereof. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  schematically shows a perspective view of an embodiment of the oral-care implement having spring-loaded cleaning elements. 
         FIG. 2  schematically shows a cross-sectional view of the oral-care implement having spring-loaded cleaning elements. 
         FIGS. 3A and 3B  schematically show fragmental cross-sectional views of the oral-care implement having a spring-loaded cleaning element in two extreme positions, wherein an angle of projection and a length of a projecting portion of the spring-loaded cleaning element changes. 
         FIG. 4  schematically shows a cross-sectional view of an embodiment of the oral-care implement having spring-loaded cleaning elements disposed in channels having differential shapes. 
         FIG. 4A  schematically shows a cross-sectional view of another embodiment of the oral-care implement having conventional cleaning elements and spring-loaded cleaning elements. 
         FIG. 4B  is a cross-sectional view taken along B-B in  FIG. 4A . 
         FIG. 5  schematically shows elastic deformation of the spring-loaded cleaning element during its use. 
         FIGS. 6A-6E  schematically show, in plan and side views, several non-limiting embodiments of the oral-care implement having different exemplary patterns of the spring-loaded cleaning elements thereon. 
     
    
    
     DETAILED DESCRIPTION 
     The following text sets forth a broad description of numerous different embodiments of the present disclosure. The description is to be construed as exemplary only; it does not purport to describe every possible embodiment or variation of the invention since describing every possible embodiment or variation would be impractical, if not impossible. It should be understood that any feature, characteristic, component, composition, ingredient, product, step or methodology described herein can be deleted, combined with or substituted for, in whole or part, any other feature, characteristic, component, composition, ingredient, product, step or methodology described herein. Numerous alternative embodiments could be implemented, using either current technology or technology developed after the filing date of this patent, which would still fall within the scope of the claims. 
     As is shown in  FIG. 1 , an oral-care implement  10  has a longitudinal axis  11  and comprises a bristle carrier  20  and a plurality of cleaning elements  30  embedded in and outwardly extending from the bristle-carrier  20 . The plurality of cleaning elements may comprise conventional (stationary) cleaning elements, such as, e.g., those comprising PA6.12 (Nylon) or PBT or elastomeric cleaning elements. Exemplary embodiments having stationary cleaning elements  30   a  are shown in  FIGS. 4A and 6A-6E . Several types of cleaning elements, e.g., are distributed by DuPont™ Corporation, such as, e.g., those under the brand name Tynex®; and by Hahl Pedex, GMBH. Non-limiting examples of suitable filaments include mixed filaments, coextruded filaments, core-and-sheath filaments, spiral filaments, surface-textured filaments, chemically tapered filaments, crimped filaments, foamed filaments, and others. A typical filament diameter may be from 4 mil to 8 mil. 
     At least one of the cleaning elements  30  is a spring-loaded cleaning element  40  movably disposed in a channel  50  formed in the bristle carrier  20 ,  FIG. 2 . The cleaning elements  30 , including the spring-loaded cleaning elements  40 , may extend from the bristle carrier at various differential angles, which may differ from one another. That is, a plurality of spring-loaded cleaning elements  40  may extend at an angle different from those of the non-spring-loaded cleaning elements. Further, the individual cleaning elements  30 , including the spring-loaded cleaning elements  40 , may extend at angles different relative to one another. 
     The individual spring-loaded cleaning element  40  may comprise a single monofilament or a tuft, as is well known in the art. The individual spring-loaded cleaning element  40  comprises a spring portion  41  disposed in the channel  50  and a projecting portion  42  longitudinally adjacent to the spring portion  41  and outwardly extending from the channel  50  at an angle of projection A 1  relative to the bristle carrier  20 ,  FIG. 3A . When pressure P is applied during use of the oral-care implement  10  (e.g., brushing), the spring portion  41  elastically deforms (buckles or bends) inside the channel  50  to at least partially conform to a shape of the channel  50 ,  FIGS. 3A and 3B . This causes the projecting portion  42  to change its length, from L 1  to L 2 , as well as the angle of projection at which the spring-loaded cleaning element  40  projects from the bristle carrier  20 , from A 1  to A 2 ,  FIGS. 3A and 3B . The channel  50  may comprise a curved portion  51  suitably shaped to facilitate the elastic deformation of the spring portion  41  of the spring-loaded cleaning element  40  inside the channel  50 . 
     In one embodiment, the channel includes a closed end  52 . In other words, the channel  50  can be structured to be a “blind” channel. The end  52  can support an embedded end  45  of the spring portion  41  disposed in the channel  50 . An open mouth  53 , disposed opposite to the closed end  52 , can be structured to facilitate a movement of the spring-loaded cleaning element  40  therethrough when the spring portion  41  elastically deforms inside the channel  50 . 
     The open mouth  53  can also be structured to cause the spring-loaded cleaning element  40  to form a desired angle of projection A when the spring portion  41  elastically deforms inside the channel  50 . Thus, the open mouth  53  can be configured to allow a movement of the spring-loaded cleaning element  40  through the open mouth  53  resulting in a change of the angle of projection of the projecting portion  42  of the spring-loaded cleaning element  40 ,  FIGS. 3A, 3B . 
     In other embodiments (not shown) the channel  50  can be open from both ends, to facilitate removal of water, dentifrice, particles, and the like from the oral-care implement  10 . In such an embodiment, the embedded end  45  can be supported inside the channel  50  by other means, such as, e.g., mechanically or adhesively. 
     In some embodiments, the oral-care implement  10  may comprise a shaft  60  connected to the spring-loaded cleaning element  40 . In such embodiments, the channel  50  may include a travel path  61  structured to receive the shaft  60  for movement along the travel path  61 ,  FIG. 3B . The shaft  60  can be connected to the spring-loaded cleaning element  40 , i.e., intermediate its embedded end and its free end,  FIG. 3B . In use, a movement of the shaft  60  along the travel path  61  facilitates elastic deformation of the spring-loaded cleaning element  40  inside the channel. The travel path  61  can be suitably sized and configured to allow the shaft  60  to move back and forth (up and down in  FIG. 3B ) under the influence of pressure P periodically applied to the spring-loaded cleaning element  60  during use of the oral-care implement. The force P forces the shaft  60  to move inside the channel  50  along the travel path  61 , thereby forcing the spring portion  41  to deform inside the channel  50 . As is best shown in  FIG. 3B , the elastic deformation of the spring portion  41  inside the channel  50  can occur in accordance with a predetermined pattern based on the shape of the curved portion of the channel  50 . 
     In embodiments in which the oral-care implement  10  comprises a plurality of spring-loaded cleaning elements embedded in and outwardly extending from the bristle-carrier  20 , each of the spring-loaded cleaning elements  40  can be disposed in its respective channel  50  formed in the bristle carrier  20 . Each of the spring-loaded cleaning elements  40  can be structured and configured to elastically deform inside the channel  50 , wherein angles of projection at which individual spring-loaded cleaning elements  40  outwardly extend from the bristle carrier  20  change, either uniformly or non-uniformly, as the spring-loaded cleaning elements  40  elastically deform inside their respective channels  50 . 
     In a further embodiment, the angles of projection, at which the individual spring-loaded cleaning elements  40  outwardly extend from the bristle carrier  20 , may differ from one another,  FIG. 4 . In another embodiment, the angles of projection may change non-uniformly relative to one another,  FIG. 4 . Such a non-uniform change of the angles of projection can be caused or influenced, e.g., by differential shapes of the channels  50 . The differential shapes of the channels can cause differential elastic deformation of the spring-loaded cleaning elements  40 . 
     In  FIG. 4 , e.g., an embodiment of the oral-care implement  10  comprises a first channel  50   a  and a second channel  50   b , wherein the first channel  50   a  has a first shape and the second channel  50   b  has a second shape different from the first shape. A first spring-loaded cleaning element  40   a  is disposed in the first channel  50   a , and a second spring-loaded cleaning element  40   b  is disposed in the second channel  50   b . The first channel  50   a  is configured to facilitate a first elastic deformation of the first spring-loaded cleaning element  40   a , and the second channel  50   b  is configured to facilitate a second elastic deformation of the second spring-loaded cleaning element  40   b . Since under pressure the spring portions  41   a ,  41   b  of the respective first and second spring-loaded cleaning elements  40   a ,  40   b  tend to at least partially conform to the shape of their respective channels  50   a ,  50   b , the first elastic deformation will be different from the second elastic deformation. This will result in the change of the angle of projection of the first spring-loaded cleaning element  40   a  being different from the change of the angle of projection of the second spring-loaded cleaning element  40   b ,  FIG. 4 . 
     In other embodiments, non-uniform changes of the angles of projection can be caused, e.g., by differential shapes and/or sizes of the travel path  61  (not shown). In still other embodiments, non-uniform changes of the angles of projection can be caused or influenced by variations in physical characteristic of the individual spring-loaded cleaning elements  40 . These physical characteristics may include, e.g., the cleaning elements&#39; length, thickness, geometry, cross-sectional shape, area moment of inertia, stiffness, elasticity, surface energy, chemical composition, color, and the other relevant characteristics. 
     In several illustrations of the invention, the spring-loaded cleaning elements  40  are schematically depicted as comprising generally solid elastomer bodies, shaped and arranged for optimal cleaning. Examples of suitable elastomer bodies and their configurations can be found, e.g., in U.S. Pat. No. 6,553,604; U.S. Pat. No. 6,151,745; U.S. Pat. No. 5,987,688; U.S. Patent Application Publications No. 2004/0177462 filed on Mar. 14, 2003 and U.S. Patent Application Publications No. 2005/0235439 filed on Apr. 23, 2004. 
     In other embodiments, the spring-loaded cleaning elements  40  are schematically depicted as including a plurality of bristles, forming a tuft,  FIG. 4 . In further embodiments of the oral-care implement, the spring-loaded cleaning elements  40  may comprise both the spring-loaded cleaning elements  40  made of solid elastomer bodies and the spring-loaded cleaning elements  40  comprising a plurality of bristles forming a tuft. In other embodiments, the individual spring-loaded element  40  may comprise a spring portion  41  formed by a solid elastomer or other material, and the projecting portion  42  comprising a plurality of bristles forming a tuft and longitudinally connected to the solid spring portion  41 ,  FIG. 4 . Embodiments comprising a reversed implementation of the individual spring-loaded cleaning element  40  are contemplated as well. 
     The spring-loaded cleaning element  40  may comprise a uniform structure or composition, wherein both the spring portion  41  and the projecting portion  42  comprise an essentially identical material. In another embodiment, the spring-loaded cleaning element  40  may comprise a composite structure, wherein the spring portion  41  comprises a first element and the projecting portion  42  comprises a second element,  FIGS. 4 and 4A . In such an embodiment, the spring portion  41  can be longitudinally attached to the projecting portion  42  by any means known in the art, e.g., overmolding of the filaments in the tuft, gluing and welding, e.g., laser-welding, or by manufacturing the spring portion  41  and the projecting portion  42  in a multicomponent molding process. In one particular embodiment, the spring portion  41  can be attached to the projecting portion  42  by the shaft  60 ,  FIG. 3B . 
     Non-limiting examples of the composite spring-loaded cleaning element  40  include those in which the spring portion  41  and the projecting portion  42  comprise the following combinations: 
     
       
         
           
               
               
             
               
                   
               
               
                 Spring Portion 
                 Projecting Portion 
               
               
                   
               
             
            
               
                 PA (polyamide) 
                 PA, TPE (thermoplastic elastomer) 
               
               
                 PP (polypropylene) 
                 TPE 
               
               
                 POM (polyoxymethylene) 
                 TPE, PA 
               
               
                 TPE 
                 TPE, PA 
               
               
                 ABS (acrylonitrile  
                 TPE 
               
               
                 butadiene styrene) 
               
               
                   
               
            
           
         
       
     
     Embodiments are contemplated where the spring-loaded cleaning elements  40  comprise elastomeric elements commonly known as “fins,” such as those, e.g., disclosed in U.S. Pat. No. 6,553,604 or U.S. Patent Application Publication No. 2005/0235439. The fins may comprise either one or both of the spring portion  41  and the projecting portion  42  of the spring-loaded cleaning element  40 —and may be structured to be fitted into the channels  50  or attached, e.g., mechanically or adhesively, to the spring portion  41 . 
     In an exemplary embodiment of  FIG. 4 , e.g., each of the shown spring-loaded cleaning elements  40   a  and  40   b  comprises the spring portion  41   a ,  41   b  that is solid and the projecting portion  42   a ,  42   b  that comprises a plurality of conventional bristles forming a tuft. Likewise, in another exemplary embodiment shown in  FIG. 4A , a spring-loaded cleaning element  40   c  comprises a spring portion  41   c  that is formed by a solid-mass material and a projecting portion  42   c  that comprises a tuft formed by a plurality of individual bristles. 
     The embodiment shown in  FIG. 4A  also includes a spring-loaded cleaning element  40   d  that comprises a spring portion  41   d  and a projecting portion  42   d , wherein the spring portion  41   d  differs from the projecting portion  42   d  in at least one physical characteristic selected from the group consisting of length, thickness, geometry, cross-sectional shape, area moment of inertia, stiffness, elasticity, surface energy, chemical composition, color, and any combination thereof. As is best shown in the cross-sectional view of  FIG. 4B , the spring portion  41   d  has an overall diameter that is greater than that of the projecting portion  42   d . In addition, the spring portion  41   d  has an X-shaped cross-section, whereas the projecting portion  42   d  has a generally round cross-section. One skilled in the art will appreciate that various combinations of the shapes can be suitable, all of which are included in the scope of the present disclosure. In the exemplary embodiment of  FIG. 4A , there are shown at least two conventional tufts  30   a , each comprising a plurality of individual bristles. These tufts  30   a  are shown as having different inclination angle relative to the longitudinal axis  11  of the implement. 
     In the exemplary embodiment of the oral-care implement shown in  FIG. 4A , the spring portion  41   c  of the spring-loaded cleaning element  40   c  may differ from a corresponding spring portion  41   d  of the spring-loaded cleaning element  40   d  in at least one physical characteristic selected from the group consisting of length, thickness, geometry, cross-sectional shape, area moment of inertia, stiffness, elasticity, surface energy, chemical composition, color, and any combination thereof. Likewise, the projecting portion  42   c  of the spring-loaded cleaning element  40   c  may differ from a corresponding projecting portion  42   d  of the spring-loaded cleaning element  40   d  in at least one physical characteristic selected from the group consisting of length, thickness, geometry, cross-sectional shape, area moment of inertia, stiffness, elasticity, surface energy, chemical composition, color, and any combination thereof. 
     Not wishing to be bound by a theory, the inventors believe that  FIG. 5  schematically shows a movement, in a direction of an arrow C and relative to the user&#39;s teeth  90 , of the oral-care implement of the disclosure, comprising the spring-loaded cleaning element  40 . In a step A, the free end of the spring-loaded cleaning element  40  contacts the surface of the toot. In step B, the movement of the oral-care implement and the teeth&#39;s topography causes the spring portion of the spring-loaded cleaning element  40  to flex, or elastically deform, inside the channel  50 , as is described herein. In steps C and D, as the oral-care implement travels further relative to the teeth, the projecting portion of the spring-loaded cleaning element may also elastically deform as its free end scratches the surface of the tooth, whereas the contact with the tooth is maintained. In steps E and D, during further movement, upon reaching an interdental gap  91 , the spring-loaded cleaning element  40  suddenly releases its energy accumulated during its elastic deformation. 
     In other words, the spring-loaded element  40  is structured and configured to dynamically “kick” into the interdental gap  91 . This will facilitate a more efficient interruption of a plaque layer existing on the surface of the teeth, and particularly in the otherwise hard-to-reach interdental gap. This will also allow the cleaning elements to achieve a deeper penetration between the teeth. In addition, it is hypothesized that the ability of the spring-loaded cleaning element to flex inside the channel will beneficially result in an increased contact time between the free end, or tip, of the spring-loaded element and the surface of the teeth, relative to that of conventional (stationary) cleaning elements. The ability of the spring-loaded cleaning elements to flex inside the channels, thereby changing their projected lengths and angles of projection, will also facilitate the spring-loaded cleaning elements&#39; adaptability to the individual topography of the user&#39;s mouth and teeth, thereby promoting a more comfortable feeling by the user during brushing, including increased comfort with respect to the user&#39;s gums. 
     The brushing forces on a toothbrush during brushing can be in a range between about 0.5 N and about 10 N dynamically—and typically between about 2 N and about 4 N, considering the entire brush. An individual filament or tuft carries only a portion of the complete brush force. The buckling of the individual spring-loaded cleaning element  40  occurs within the range of the typical brushing forces, preferably up to 2 N, to avoid the risk of damage to the user&#39;s gums. The buckling force of an individual spring-loaded cleaning element  40  can be in the range of from about 0.01 N to about 2 N. Depending on the material properties (e.g., influencing young modulus) and the shape of the cross-sectional area of the spring-loaded cleaning element  41  (e.g., influencing moment of inertia) the dimensions of the spring-loaded cleaning element  41  can be defined to achieve the desired buckling force requirement. 
     For a round-shaped element, the buckling force can be defined in the following manner: 
                 F   k     =         π   2     ⁢   EI       s   2         ,         
where
 
     “E” is a young modulus; “I” is a moment of inertia, wherein I=π/4+R 4 ; and “s” is a length. As the length of the cleaning element is typically relatively short in the brush head and the cross-sectional area is defined, among other things, by available space in the brush head, the suitable material can be chosen to fulfill the requirement of the buckling force to be greater than 0.01 N, or F k &lt;(0.01−2.0)N. 
     For example, a spring element having a length of about 4 mm, a young modulus E of about 3400 MPa, and a diameter d of about 0.25 mm would require roughly 0.4 N to buckle. Softer materials may be chosen for thicker elements to keep the buckling forces low. In order to keep the pressure on the soft tissues in a desired range, the respective diameters of the spring portion  41  and of the projecting portion  42  may be different. For example, low pressure on the user&#39;s gums by the spring-loaded cleaning element  40  can be achieved by having a larger cross-sectional area of the projecting portion  42  relative to the cross-sectional area of the spring portion  41 . 
     Several exemplary patterns of the spring-loaded cleaning elements  40 , and conventional stationary elements  30   a , are shown in  FIGS. 6A-6E .  FIGS. 6A-6D  schematically illustrate the oral-care implement  10  comprising a manual toothbrush.  FIG. 6E  schematically illustrates, in plan view, the oral-care implement  10  comprising a refill for an electric toothbrush. One skilled in the art will recognize that many other suitable configurations and combinations of patterns can be had. All of these patterns and combinations are included in the scope of the present disclosure. 
     The disclosure of every document cited herein, including any cross-referenced or related patent or application and any patent application or patent to which this application claims priority or benefit thereof, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein—or that it alone, or in any combination with any other reference or references, teaches, suggests, or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same or similar term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern. 
     While particular embodiments have been illustrated and described herein, various other changes and modifications may be made without departing from the spirit and scope of the invention. Moreover, although various aspects of the invention have been described herein, such aspects need not be utilized in combination. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of the invention.