Abstract:
An apparatus for confining in a fastening member articles resting on a surface including a housing with a cavity for holding an open fastening device and a control arm linked to first and second members, the control arm being movable between a start position and an end position to successively actuate the first and second members. The first member is adapted to contain and lift the article into position to await delivery of the open fastening device and the second member is adapted to deliver the open fastening device to the article and to close the fastening device to confine the article. In one important embodiment, the first member is also adapted to raise the apparatus away from the surface.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates generally to an apparatus and a method for fastening at least two articles to one another and, more particularly, to an apparatus and a method for rapidly and efficiently lifting, delivering and confining in an adjacent relationship within a fastening device and then fastening portions of at least two relatively rigid, generally cylindrical articles. 
       BACKGROUND OF THE INVENTION 
       [0002]    It is sometimes necessary to confine portions of relatively rigid generally cylindrical articles in a close relationship during the formation of a final product, so that relative movement is limited while the final product is being formed. For example, when radiant heating tubing is to be provided within a concrete driveway, a supporting network in the form of a wire mesh is laid in place and radiant heating tubing is then attached to the wire mesh as it is advanced over portions of the wire mesh in a desired, usually serpentine, relationship. Conventionally, this attachment is accomplished with wire ties or nylon ties that are wrapped around portions of the wire mesh and adjacent portions of the radiant heating tubing before the concrete is poured and cures to form the driveway. Where additional strength is required, conventional rebar may be added to the wire mesh or used in place of the wire mesh. In other types of construction, where conventional rebar is used to strengthen structures made of concrete, rebar sections are attached together using conventional ties as or before they are moved into the desired location before pouring the concrete to form the structures. 
         [0003]    The application of such conventional ties is backbreaking work that is time consuming and can produce unreliable inconsistent results where ties are attached in a haphazard way or even are skipped to minimize the labor. Also, in some applications a polystyrene foam board is placed below the tubing and mesh. Prior tools for applying fastening devices to attach tubing to supporting networks fail to deliver consistently satisfactory results, frequently jam, and risk damaging the tubing (and the foam board where used), and impairing the functionality of the tubing. Also, prior tools cannot tolerate irregularities in the underlying surface or a soft substrate like foam board and are slow and cumbersome to use. 
         [0004]    Fastening devices in the form of locking clips that are particularly suitable for the above applications were recently developed by the present inventor, Peter G. Mangone, Jr., and are described in his U.S. Pat. Nos. 6,298,549; 6,606,786; and 6,779,241, the teaching and contents of which are incorporated herein by reference. The locking clips described in these patents (referred to in the above-noted patents as “devices for forming an enclosure”), may be generally described with reference to  FIG. 1 . 
         [0005]    Thus, the locking clips  10  of  FIG. 1  include two side members,  12  and  14 , having respective inner and outer side faces,  12 A,  12 B,  14 A, and  14 B. The two side members are generally curved as shown and have upper body portions  16  and  18  that are pivotally connected by a pivot member  20 . Side members  12  and  14  have abutment portions  22  and  24  extending outwardly from the outer side faces of each of the members. Inwardly pivoting motion is achieved by applying a generally downward force to the top surfaces  34  and  36  of each of abutment portions  22  and  24  as the locking clips come into contact with the tubing (as shown for example in  FIGS. 4B to 4D  below). 
         [0006]    Pivot member  20  may be a living hinge (as shown) or it can be another pivoting member as described in the above-noted patents. The pivot member clearance area  38  enables pivotal motion of the side members in substantially parallel planes from an open/receiving position to a closed/locked position. The side members are designed to lock in the closed position by way of locking portions at or near the distal ends of the side members. Preferably, once engaged the locking portions will be irreversibly locked. The locking portion of one of the two members may comprise a flexible end portion such as shown at  26  including a recess  30 . The locking portion of the other of the two members may have a protruding end portion such as shown at  28  with a hook portion  32  configured to mate with recess  30 , where the flexible end portion and the protruding end portion are located and configured so that application of force on the abutment portions moves the locking portions together whereupon hook member  32  enters recess  30  to irreversibly mate the locking portions. Other closing or locking configurations can be used. 
         [0007]    Inner side faces  12 A and  14 A of members  12  and  14  define a fully circumscribed opening  168  ( FIG. 4D ) when the side members are in the locked position. The details of the locking member of  FIG. 1  as well as other locking members are described in the aforementioned &#39;549, 786 and &#39;241 patents which, as indicated earlier, are incorporated by reference. Also, it should be noted that the present invention may be used with other fastening device designs so long as the fastening devices include interlocking pivoting side members and abutment portions for applying an inwardly closing force to the side members. 
         [0008]    The &#39;549, &#39;786 and &#39;241 patents describe an apparatus for moving a locking clip such as that of  FIG. 1  from the open position to the closed position, to enclose, for example, at least two relatively rigid articles using a tool. The tool described includes a feed track that supports a row of locking clips in their open position and urges the locking clips toward an end plate of the tool where the leading locking clip is urged against the end plate. The end plate has a generally planer surface and a guide projecting outwardly from the planer surface toward the row of clips. The guide includes the first guiding surface and, spaced therefrom, a second guiding surface. In the tool, the clips are urged against the end plate so that a portion of at least one of the two members of the clip is facing one of the first and second guiding surfaces and a portion of the other of the two members is facing the other of the first and second guiding surfaces. 
         [0009]    The above tool has means as described in the patents for applying force to the abutment portions of the spaced apart portions of the clip. The force applying means of this prior art apparatus is located relative to the abutment portions so that the force applying means contacts the abutment portions of the clips to move them from the opened position to the closed position confining the two relatively rigid members between the inner surfaces of the clip. 
         [0010]    The present invention is directed to an improved apparatus and method for confining portions of at least two relatively rigid, generally cylindrical articles in an adjacent relationship using a fastening device with interlocking pivoting members movable from an opened position to a closed position. The apparatus and method: 1) contain and lift the articles away from the surface on which they rest; 2) raise the body of the apparatus away from the surface; 3) deliver the fastening device into position to confine the articles; 4) safely and efficiently secure the fastening device in the closed position about the articles; and 5) expeditiously release the closed fastening device and articles from the apparatus. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a front elevation view of a prior art locking clip which may be used in the practice of the present invention; 
           [0012]      FIG. 2  is an elevation view of the back of an apparatus in accordance with the present invention; 
           [0013]      FIG. 3  is a front elevation view of the front of an apparatus in accordance with the present invention; 
           [0014]      FIGS. 4A-4D  are representations of the distal end portion of an apparatus in accordance with the present invention showing various stages in the clip closing and locking operation of the apparatus; 
           [0015]      FIG. 5  is a partial top perspective view of a clip holding magazine of an apparatus in accordance with the present invention; 
           [0016]      FIGS. 6A and 6B  are respectively front and back views of the bottom plate of the magazine of  FIG. 5 ; 
           [0017]      FIG. 7  is a perspective view of a grabber arm which may be used in the apparatus of  FIGS. 1 and 2 ; 
           [0018]      FIGS. 8A-8D  are representations of the action of grabber arms which may be used in the practice of the present invention; 
           [0019]      FIGS. 9A and 9B  are respectively front and back perspective views of a clip driver which may be used in the practice of the present invention; 
           [0020]      FIG. 10  is a back perspective view of a body plate of an application section of an apparatus which may be used in accordance with the present invention; 
           [0021]      FIG. 10A  is a partial back perspective view of an alternative application section of an apparatus that may be used in accordance with the present invention in which fingers with broad flat ends are used; 
           [0022]      FIG. 11  is a cover intended to be joined to the body plate of  FIG. 10 ; and 
           [0023]      FIG. 11A  is a perspective view of a spring loaded detent intended to be mounted in the cover of  FIG. 11 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0024]    A complete grasping and fastening apparatus  100  in accordance with the invention is illustrated in  FIGS. 2 and 3 . Apparatus  100  includes an application section or housing  102  that includes means as described below for containing and lifting relatively rigid generally cylindrical articles away from the surface supporting the articles, raising the body of the apparatus, delivering a locking clip into position to confine the articles, securing the clip in the closed position, and releasing the locking clip and articles from the apparatus. The apparatus also includes a magazine  104  for holding a plurality of locking clips and feeding those clips into the application section. Finally, the apparatus includes a push rod  106  for actuating the application section and carrying out the method of the invention. 
         [0025]    The clip closing and locking operation of fastening apparatus  100  of the present invention is illustrated in  FIGS. 4A-4D . These figures represent a view of the distal end portion of body  108  of the application section. As shown in these figures, body  108  includes a cavity  110  in its outer surface  112  in which a leading locking clip  114  is shown positioned and ready to be closed and locked, and fingers  116  and  118  at the end of the application section. Cavity  110  includes a lower sill  128 . It also has an upper boundary  130  that is scalloped to clear the upper edge of the clip (as shown in  FIG. 10 ) to enable successive clips to enter into cavity  110 . In  FIGS. 4A-4D , the scalloped upper boundary has been removed to help illustrate the clip closing and locking operation. 
         [0026]    Fingers  116  and  118  include radiused distal ends  120  and  122  separated by a cavity  124 . In the illustrated embodiment, the curved edges of the fingers gently curve into cavity  124  which is radiused at its top  126 . In alternative embodiments, cavity  126  may be of other configurations. Also, distal ends  120  and  122  of fingers  116  and  118  may be of other configurations. For example, the fingers may taper downwardly to form a sharp point, a narrow flat tip, a broad flat end, or the distal ends of the fingers may be of other shapes, as desired. One such alternative design is shown in  FIG. 10A  where fingers  116 A and  118 A have broad flat ends  120 A and  122 A. 
         [0027]      FIGS. 4A-4D  show a portion of arms  140  and  142  of driver  138 , which is more fully described and illustrated in connection with  FIGS. 9A-9B . Arms  140  and  142  each have leading faces  144  and  146 . Clip  114  includes outer members  148  and  150  pivotally connected at their proximal end by a pivot member in the form of a living hinge  152 . The outer members have abutment portions  154  and  156  projecting generally outwardly from the outer surfaces of each of the clip members for engagement by leading flat faces  144  and  146  of driver  138 . Additionally, the distal ends of the clip members have first and second interlocking portions  158  and  160 . Finally, the outer leading edges  159  and  161  of the outer members are curved toward the centerline of the clip. 
         [0028]    Turning now to  FIG. 4A , clip  114  is shown ready for application, with driver arms  140  and  142  adjacent to abutment portions  154  and  156 . Two relatively rigid generally cylindrical articles are shown in cross section in the area between the clip arms in the form of rubber radiant heating tubing  144  (e.g., PEX tubing) and steel wire mesh  164 . The top of the cavity  126  in this preferred embodiment has a radius generally corresponding to the outer radius of the upper radiant heating tubing  162  enabling it to rest snugly at the top of the cavity. Finally, distal ends  120  and  122  of fingers  116  and  118  are shown resting against a generally flat surface  166  such as a polystyrene foam board on the surface of a driveway before application of concrete (not shown) which is to cover the radiant heating tubing and wire mesh. It should be noted that in many applications the supporting surface will be irregular or strewn with aggregate or debris. 
         [0029]    In  FIG. 4B , driver arms  140  and  142  are shown partially advanced to move the clip downwardly (past a detent as will be explained in further detail below), placing it in an ideal position vis à vis the wire mesh and radiant heating tubing which has been lifted up into cavity  124  in an earlier step in the use of the apparatus. As can be seen in this figure, the inner surface of the clip engages the radiant heating tubing to limit further downward movement of the clip. 
         [0030]    Next, in  FIG. 4C , the driver is shown advanced further downward with arms  140  and  142  pressing against abutment portions  154  and  156  causing outer members  148  and  150  to pivot inwardly until interlocking portions  158  and  160  just touch. As can be seen in this figure, the interlocking members clear surface  166  below the fingers. 
         [0031]    Finally, in  FIG. 4D , clip driver  138  is shown advanced to its lowermost position, causing the interlocking portions to irreversibly interlock as shown. This produces a fully circumscribed opening  168  between the outer members, confining the radiant heating tubing and wire mesh in an adjacent relationship. In a preferred embodiment, corners  163  of the clips are rounded to minimize the likelihood that the clips will catch on the supporting Surface or debris present thereon as the side members pivot inwardly to the closed position. 
         [0032]    In practice, the steps of  4 A through  4 D are preferably performed in a continuous, even motion. (Indeed, as discussed below, the full range of the operation of apparatus  100  is preferably accomplished with continuous, even motion.) Also, the size of the clip in its closed position vis a vis the outer diameters or cross-sections of the confined articles will determine how snugly the confined articles are held in the confining opening. Therefore, if a snugger fit is desired, a smaller clip will be used. Finally, while the present invention is considered ideal for use in confining relatively rigid generally cylindrical articles (like rubber hose, wire, metal rods, etc.) in an adjacent relationship, it may be used with articles of other shapes and indeed, it may also be used with articles that are not relatively rigid. 
         [0033]      FIG. 5  is a top view of magazine  104  of apparatus  100 . In this view, inner tube supports  170  and  172  and outer tube supports  174  and  176  are seen in end view, welded to tube supports  178 . Tube supports  178  include notches  180  to provide clearance for the clips as they are inserted and move into position as the magazine is loaded. Thus, one such clip  114  is shown in  FIG. 5  with the proximal tips  182  and  184  of each of its outer members  148  and  150  resting in notch  180  and abutment portions  154  and  156  resting in the space between the pairs of adjacent inner and outer support tubes. A series of clips (not shown) will be loaded into the magazine so that they slide down along the inner and outer tube supports with the leading clip resting in application section  102  and succeeding clips abutting each other and extending upwardly from the end of the magazine along the inner and outer support members. This insures a supply of clips which can be quickly applied in successive locations as desired by the tool operator. While the clips will move into place and remain ready to be fed into the apparatus under the force of gravity, the clips may also be positioned and fed by applying a spring loading (not shown) against the topmost clip in the magazine. 
         [0034]    As can be seen in  FIG. 2 , the magazine tube supports are fastened (for example by welding as shown) to a bottom plate  186  that is attached to the outer surface  112  of body  108  of the application section. Bottom plate  186  is shown in front and back views respectively in  FIGS. 6A and 6B . Thus, the front surface  188  of the bottom plate is generally flat and includes holes for accepting screws for attaching the plate to the outer surface  112  of the application section. The plate is scalloped along its upper boundary  130  to admit clips past the plate into the body of the application section, with clip abutment portions  154  and  156  passing through slots  190  and  192  in the plate and the top of the clip clearing the central scallop at point  194 . Finally, plate  186  includes two inwardly directed fingers  196  and  198  which protrude from the back surface  200  of the plate. These fingers have flats  202  and  204  set back from the outer edges  206  and  208  of the plate to facilitate positioning of the plate in cavity  110  of the application section. The generally flat back faces  210  and  212  of fingers  196  and  198  are spaced from back cover  304  ( FIG. 11 ) and cooperate with detents  370  located opposite the finger faces to hold successive clips in place until needed, as will be explained below. 
         [0035]    Turning the apparatus over to the view shown in  FIG. 3 , two overlapping grabber arms  300  and  302  are shown pivotally attached to cover  304  of body  108  of application section  102 . Each of the grabber arms is a generally identical mirror image of the other. Thus, a representative grabber arm  300  is illustrated in  FIG. 7  and includes a control section  305  and a lifting section  306 . The control section has a broad generally V-shaped slot  308  which runs from the top outer corner  310  of the grabber arm to the mid-inner surface  312  of the control section and back toward the bottom outer edge  314  of the control section. A pivot hole  316  is positioned in the lower inner corner  318  of the control section. 
         [0036]    Lifting section  306  includes a guide surface  320  beginning with a chiseled end  322  having a leading bevel  324 , followed by a trailing bevel  326  and a generally curved surface  328  leading to a radiused opening  330 . (In the illustrated embodiment, opening  330  is dimensioned to accept tubing  162 ). Ends  322  may be radiussed or beveled to minimize potential interference with substrates like polystyrene foam board. The grabber arms are mounted for overlapping pivotal movement by a pivot pin  332  ( FIG. 3 ) that passes through the pivot holes  316  of the two grabber elements. Also, bore  331  accepts a guide pin  333  that engages arcuate slot  394  ( FIGS. 1 &amp; 11 ) in the cover of the application section. 
         [0037]    The action of the grabber arms  300  and  302  is illustrated in  FIGS. 8A-8D . Thus, apparatus  100  is positioned on surface  166  bearing articles (not shown) that are to be confined in a clip to be applied with the device. As a downwardly directed force is applied to the apparatus (as described below), the grabber arms pivot inwardly to the position shown in  FIG. 8B , so that chiseled ends  322  clear the inner edge  334  running along cavity  124 . The chisel tips of the grabber arms are thus poised to initially engage the larger diameter heating tubing  162  ( FIG. 4A ). The grabber arms continue pivoting to ride under the wire mesh below the tubing reaching the position shown in  FIG. 8C  where the chisel tips are opposite each other. 
         [0038]    At this point, the grabber arms contain the heating tubing and wire mesh portions which have been lifted away from surface  166  by the scissors action of the grabber arms. The articles are then held in a capture area between the grabber arms, above the inwardly directed distal ends of the grabber arms. As can also be seen in this figure, the grabber arms have begun to lift the entire apparatus away from supportive surface  166  through the pivoting action of their bottom edges  336  and  338  against the supporting surface. The grabber arms continue pivoting to their final fully closed position as shown in  FIG. 8D  where the corner radii  340  and  342  of bottom edges  336  and  338  lift the apparatus to its maximum spacing from the support surface. This lifting action facilitates the scissors action of the grabber arms as they sweep around to their fully closed position and provides clearance from debris or aggregate on the supporting surface. Also, the corner radii provide secure footing for the apparatus on irregular supporting surfaces. 
         [0039]    The pivoting movement of grabber arms  300  and  302  is achieved by the cooperation of pivot pin  332  and the movement of link pins  344  and  346  that are attached to bores  360  and  362  of clip driver  138 . The clip driver thus moves the pins in slots  308  of each of the grabber arms as it also operates on clip  114 . The link pins are in the location depicted in  FIG. 3  when the grabber arms are positioned as shown in  FIG. 8A . As the link pins move downwardly in slots  348  and  350  of body cover  304  ( FIG. 11 ) they also engage the first leg  308 A of slot  308  of the grabber arms causing the arms to pivot inwardly through the stages depicted in  FIGS. 8A-8C , as the slots are re-oriented to follow the movement of the link pin. This continues until the grabber arms reach the position depicted in  FIG. 8D  and the link pins reach the transition point  308 B in the slots. At the transition point, the second legs  308 C of the slots will be aligned with slots  348  and  350 , so that further downward movement of the link pins will not produce further pivoting action of the grabber arms and will ensure that the grabber arms remain in the position depicted in  FIG. 8D . 
         [0040]      FIGS. 9A and 9B  illustrate respectively the front and back surfaces of driver  138 . As can be seen from the  FIG. 9A , the back surface  352  of driver  138  is generally flat. An attachment member  353  extends upwardly from the top of the driver and has a recess  354  for receiving and attaching the distal end of push rod  106  to the driver. Driver  138  has two downwardly directed arms  140  and  142 , and ears  356  and  358  that project into the space between the arms. These ears have threaded bores  360  and  362  that accept threaded link pins  344  and  346  to operate the grabber arms as described above. 
         [0041]    Turning to the front of the driver in  FIG. 9B , it is seen that the front surface  364  of the driver has standing ribs  366  and  368  that mesh with slots in body cover  304  of application section  102  ( FIG. 11 ). Additionally, the outer edges of the back surface of each of the arms has been undercut to provide open clearance slots  370  and  372  for detents  370  ( FIG. 11A ) that hold the locking clips in place in the apparatus before they are applied. 
         [0042]    Turning now to  FIG. 10 , the body plate  374  of application section  102  is shown. The body plate includes a central slot  376  permitting up-and-down movement of the push rod and a cut-out  378  for receiving the driver  138  in its topmost unengaged position, in which the top edge  380  of the driver ( FIGS. 9A-9B ) engages the top edge  382  of the cavity under the urging of the spring loading of the controller arm. 
         [0043]    This spring loading is provided by a coil spring  384  that encircles rod  106  between the top edge  386  of application section  102  and a collar  388 , as illustrated in  FIGS. 2 and 3 . In order to operate grasping and fastening apparatus  100 , the user places application section  102  in position and presses down on knob  390  at the proximal end of rod  106  to move the rod downwardly from the resting position shown in  FIGS. 2 and 3  until the operation of the apparatus is completed. The user then permits the rod to return to its resting position under the force of spring  384 . 
         [0044]      FIG. 11  shows body cover  304 , as viewed from the inside. The body cover includes a clearance slot  392  for the push rod corresponding to slot  376  in back plate  372 . An arcuate through slot  394  is formed in the body cover to receive guide pins  333  of the grabber arms to guide the arms in the desired pivoting motion. The body cover also has a threaded pivot bore  396  for attaching pivot pin  332 . Additionally, parallel slots  398  and  400  are located adjacent the elongated outer edges  402  and  404  of the body cover. These slots receive ribs  366  and  368  of the driver to ensure that it moves up and down within the grabber body consistently and in a direction parallel to the longitudinal axis and the elongated sides of the device. Additionally, there are parallel through slots  348  and  350  in the body cover positioned inside of the outer slots, spaced apart a distance corresponding to the spacing between threaded bores  360  and  362  in ears  356  and  358  of the driver to accept link pins  344  and  346 . Finally, spring loaded detents  370  ( FIG. 11A ) are fitted into threaded bores  372  and  374  in the body cover. These detents cooperate with flat back faces  210  and  212  of plate  186  to prevent premature clip release thereby ensuring that the leading clip is in position ready to be applied when needed. Thus, when driver  138  engages the leading clip, it initially pushes the clip past the resistance provided by the spring loaded detents. Open slots  402  and  404  in driver  138  ( FIG. 9B ) permit the driver to move downwardly past the detents without interference. 
         [0045]    The operation of grasping and fastening apparatus  100  may proceed as described below, in a continuous even motion from step 1 through step 6.
       1. A series of clips corresponding to leading clip  114  are loaded in magazine  104 , and move downwardly in the magazine until the leading clip is resting in application section  102  against detents  370 .   2. Relatively rigid, generally cylindrical articles are provided on a supporting surface.   3. Grasping and fastening apparatus  100  is positioned over the articles so that the articles generally reside in the space between fingers  116  and  118 , with the distal ends  120  and  122  of the fingers resting on the supporting surface.   4. The operator then presses down upon knob  390 , moving control rod  106  downwardly and causing clip driver  138  to move downwardly and link pins  344  and  346  also to move downwardly in slots  348  and  350  of body cover  304 , while engaging slots  308  of the grabber arms. This causes the grabber arms to pivot inwardly and engage the bottommost article resting on the supporting surface. The articles are contained in the space between the grabber arms as the grabber arms lift the apparatus away from the supporting surface.   5. As the control arm continues to be pressed downwardly, driver arms  140  and  142  of driver  138  engage abutment portions  154  and  156  of leading clip  114 , causing the leading clip to move past detents  370  until it engages the topmost article. As the locking clips come into engagement with the tubing, the continued downward movement of driver  138  causes the side members of clip  114  to pivot inwardly through the stages depicted in  FIGS. 4B-4D  until the clip is locked about the members as shown in  FIG. 4D .   6. The user then releases the apparatus by permitting the control arm to return to the position depicted in  FIGS. 2 and 3  under the force of spring  384 , lifts the apparatus away from the now clipped intersection thereby releasing the clips and articles, and moves to the next location requiring application of a clip.       
 
         [0052]    While the apparatus of the present invention is illustrated as manually operable, the control arm may be supplied with an automatic hydraulic or pneumatic driver which would move the control arm through the motion described above, albeit under hydraulic or pneumatic force initiated through a separate control or switch. In yet another alternative embodiment, a crank-up spring loaded system may be provided by which the operator loads up a spring with a potential application force and then releases that force to drive the control arm through the operation as described above. 
         [0053]    All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein. 
         [0054]    The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention. 
         [0055]    Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.