Patent Publication Number: US-2023159198-A1

Title: Strapping tool

Description:
PRIORITY 
     This application is a continuation application of U.S. patent application Ser. No. 18/003,366, having a 371(c) filing date of Dec. 27, 2022 and which is a national phase application of PCT/US2021/040834, filed on Jul. 8, 2021, which claims priority to and the benefit of U.S. Provisional Patent Application No. 63/050,965, filed Jul. 13, 2020, and U.S. Provisional Patent Application No. 63/196,391, filed Jun. 3, 2021, the entire contents of both of which are incorporated herein by reference. 
    
    
     FIELD 
     The present disclosure relates to strapping tools, and more particularly to strapping tools configured to tension strap around a load and to attach overlapping portions of the strap to one another to form a tensioned strap loop around the load. 
     BACKGROUND 
     Battery-powered strapping tools are configured to tension strap around a load and to attach overlapping portions of the strap to one another to form a tensioned strap loop around the load. To use one of these strapping tools to form a tensioned strap loop around a load, an operator pulls strap leading end first from a strap supply, wraps the strap around the load, and positions the leading end of the strap below another portion of the strap. The operator then introduces one or more (depending on the type of strapping tool) of these overlapped strap portions into the strapping tool and actuates one or more buttons to initiate: (1) a tensioning cycle during which a tensioning assembly tensions the strap around the load; and (2) after completion of the tensioning cycle, a sealing cycle during which a sealing assembly attaches the overlapped strap portions to one another (thereby forming a tensioned strap loop around the load) and during which a cutting assembly cuts the strap from the strap supply. 
     How the strapping tool attaches overlapping portions of the strap to one another during the sealing cycle depends on the type of strapping tool and the type of strap. Certain strapping tools configured for plastic strap (such as polypropylene strap or polyester strap) include friction welders, heated blades, or ultrasonic welders configured to attach the overlapping portions of the strap to one another. Some strapping tools configured for plastic strap or metal strap (such as steel strap) include jaws that mechanically deform (referred to as “crimping” in the strapping industry) or cut notches into (referred to as “notching” in the strapping industry) a seal element positioned around the overlapping portions of the strap to attach them to one another. Other strapping tools configured for metal strap include punches and dies configured to form a set of mechanically interlocking cuts in the overlapping portions of the strap to attach them to one another (referred to in the strapping industry as a “sealless” attachment). 
     SUMMARY 
     Various embodiments of the present disclosure provide a strapping tool configured to tension metal strap around a load and, after tensioning, attach overlapping portions of the strap to one another by cutting notches into a seal element positioned around the overlapping portions of the strap and into the overlapping portions of the strap themselves. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG.  1 A  is a perspective views of one example embodiment of a strapping tool of the present disclosure. 
         FIG.  1 B  is a block diagram of certain components of the strapping tool of  FIG.  1 A . 
         FIG.  2    is a perspective view of the support of the working assembly of the strapping tool of  FIG.  1 A . 
         FIGS.  3 A and  3 B  are perspective views of the working assembly of the strapping tool of  FIG.  1 A . 
         FIG.  4 A  is a perspective view of the tensioning assembly of the working assembly of  FIG.  3 A . 
         FIG.  4 B  is a perspective view of the tensioning-assembly gearing and the tension wheel of the tensioning assembly of  FIG.  4 A . 
         FIG.  4 C  is a cross-sectional perspective view of the tensioning assembly gearing and the tension wheel of  FIG.  4 B  taken along line  4 C- 4 C of  FIG.  4 B . 
         FIG.  4 D  is an exploded perspective view of the tensioning-assembly gearing and the tension wheel of  FIG.  4 B . 
         FIG.  5 A  is a perspective view of the decoupling assembly of the working assembly of  FIG.  3 A . 
         FIG.  5 B  is a cross-sectional perspective view of the decoupling assembly of  FIG.  5 A  taken along line  5 B- 5 B of  FIG.  5 A . 
         FIG.  5 C  is an exploded perspective view of the decoupling assembly of  FIG.  5 A . 
         FIG.  5 D  is a perspective view of part of the working assembly of  FIG.  3 A  including parts of the decoupling assembly and parts of the tensioning assembly. 
         FIG.  6 A  is a cross-sectional perspective view of part of the working assembly of  FIG.  3 A  including the rocker-lever assembly. 
         FIGS.  6 B and  6 C  are perspective views of the rocker-lever assembly. 
         FIGS.  6 D and  6 E  are exploded perspective views of the rocker-lever assembly. 
         FIGS.  7 A- 7 D  are cross-sectional side views of the strapping tool of  FIG.  1 A  showing the rocker-lever assembly and the tensioning assembly in different positions. 
         FIGS.  8 A and  8 B  are elevational and perspective views, respectively, of part of the tensioning assembly and the gate assembly of the working assembly of  FIG.  3 A  and of the retaining assembly of the strapping tool of  FIG.  1 A . The tensioning assembly and the gate of the gate assembly are in their respective strap-tensioning and home positions, and the retainer of the retaining assembly is in its release position. 
         FIGS.  9 A and  9 B  are elevational and perspective views, respectively, of the part of the tensioning assembly and the gate assembly shown in  FIGS.  8 A and  8 B  and of the retaining assembly shown in  FIGS.  8 A and  8 B . The tensioning assembly and the gate of the gate assembly are in their respective strap-insertion positions, and the retaining assembly is in its retaining position. 
         FIG.  10    is a perspective view of part of the housing of the strapping tool of  FIG.  1 A  including the retainer-activation assembly of the strapping tool. 
         FIG.  11    is a perspective view of part of the strapping tool of  FIG.  1 A  with the housing removed to show the retaining assembly of  FIG.  8 A  and the retainer-activation assembly of  FIG.  10   . 
         FIGS.  12 A and  12 B  are perspective views of the retaining assembly of  FIG.  8 A  and the retainer-activation assembly of  FIG.  10    with the retainer-activation switch of the retainer-activation assembly in its deactivated and activated positions, respectively. 
         FIG.  13    is a perspective view of the retainer-activation assembly of  FIG.  10   . 
         FIG.  14    is a cross-sectional perspective view of part of the strapping tool of  FIG.  1 A  showing the retainer-activation assembly of  FIG.  10   . 
         FIGS.  15 A and  15 B  are perspective views of the sealing assembly of the working assembly of  FIG.  3 A . 
         FIGS.  15 C and  15 D  are a partially exploded perspective views of the sealing assembly of  FIG.  15 A . 
         FIG.  16 A  is an exploded perspective view of the object-blocking assembly of the jaw assembly of the sealing assembly of  FIG.  15 A . 
         FIG.  16 B  is a cross-sectional perspective view of the object-blocking assembly of  FIG.  16 A  taken substantially along the line  16 B- 16 B of  FIG.  15 C . 
         FIGS.  17 A and  17 B  are perspective views of an object blocker of the object-blocking assembly of  FIG.  16 A . 
         FIG.  18 A  is a cross-sectional perspective view of the sealing assembly of  FIG.  15 A  taken substantially along line  18 A- 18 A of  FIG.  15 A . 
         FIG.  18 B  is a cross-sectional perspective view of the sealing assembly of  FIG.  15 A  taken substantially along line  18 B- 18 B of  FIG.  15 A . 
         FIG.  18 C  is a cross-sectional elevational view of the sealing assembly of  FIG.  15 A  taken substantially along line  18 C- 18 C of  FIG.  15 A . 
         FIG.  19 A  is a cross-sectional elevational view of part of the sealing assembly of  FIG.  15 A  showing the sealing assembly in its home position and the object blocker of the object-blocking assembly of  FIG.  16 A  in its retracted position. Some components of the sealing assembly are not shown for clarity. 
         FIG.  19 B  is a cross-sectional elevational view of part of the sealing assembly of  FIG.  6 A  showing the sealing assembly moved about halfway from its home position to its sealing position and the object blocker of the object-blocking assembly of  FIG.  16 A  in its blocking position. Some components of the sealing assembly are not shown for clarity. 
         FIG.  20 A  is a perspective view of part of the sealing assembly of  FIG.  15 A . 
         FIGS.  20 B and  20 C  are opposing elevational views of part of the sealing assembly of  FIG.  15 A . 
         FIG.  21    is a perspective view of the working assembly of  FIG.  3 A  showing the drive assembly. 
         FIG.  22    is a side view corresponding to  FIG.  21   . 
         FIGS.  23 A and  23 B  are side views of the working assembly of  FIG.  3 A  showing the tensioning assembly in its strap-insertion and strap-tensioning positions, respectively. 
         FIG.  24 A  is a perspective view of the conversion assembly of the drive assembly of the working assembly of  FIG.  3 A . 
         FIG.  24 B  is an exploded perspective view of the conversion assembly of  FIG.  24 A . 
         FIG.  25 A  is a perspective view of part of the support of  FIG.  2   , part of the sealing assembly of  FIG.  15 A , and part of the conversion assembly of  FIG.  24 A  in which the effective length of the linkage of the conversion assembly is at a minimum. 
         FIG.  25 B  is a perspective view of the part of the support of  FIG.  2   , part of the sealing assembly of  FIG.  15 A , and the part of the conversion assembly of  FIG.  12 A  in which the effective length of the linkage of the conversion assembly is at a maximum. 
         FIGS.  26 A- 26 H  are side views of the support of  FIG.  2    and part of the conversion assembly of  FIG.  24 A  illustrating how the effective length of the linkage of the conversion assembly varies during the sealing cycle. 
         FIG.  27    is a diagrammatic elevational view of the strap and the seal element positioned around a load before being tensioned and sealed by the strapping tool. 
         FIG.  28 A  is a cross-sectional elevational view of part of the support of  FIG.  2    and part of the sealing assembly of  FIG.  15 A  with the sealing assembly and the jaws in their home positions. 
         FIG.  28 B  is a cross-sectional elevational view of the part of the support of  FIG.  2    and the part of the sealing assembly of  FIG.  15 A  with the sealing assembly in its sealing position and the jaws in their home positions. 
         FIG.  28 C  is a cross-sectional elevational view of the part of the support of  FIG.  2    and the part of the sealing assembly of  FIG.  15 A  with the sealing assembly in its sealing position and the jaws in their sealing positions after cutting notches in the seal element and the strap. 
         FIG.  29    is a perspective view of the notched seal element. 
     
    
    
     DETAILED DESCRIPTION 
     While the systems, devices, and methods described herein may be embodied in various forms, the drawings show and the specification describes certain exemplary and non-limiting embodiments. Not all of the components shown in the drawings and described in the specification may be required, and certain implementations may include additional, different, or fewer components. Variations in the arrangement and type of the components; the shapes, sizes, and materials of the components; and the manners of connections of the components may be made without departing from the spirit or scope of the claims. Unless otherwise indicated, any directions referred to in the specification reflect the orientations of the components shown in the corresponding drawings and do not limit the scope of the present disclosure. Further, terms that refer to mounting methods, such as mounted, connected, etc., are not intended to be limited to direct mounting methods but should be interpreted broadly to include indirect and operably mounted, connected, and like mounting methods. This specification is intended to be taken as a whole and interpreted in accordance with the principles of the present disclosure and as understood by one of ordinary skill in the art. 
       FIGS.  1 A and  1 B  show one example embodiment of the strapping tool  50  of the present disclosure (sometimes referred to as the “tool” in the Detailed Description for brevity) and certain assemblies and components thereof. The strapping tool  50  is configured to carry out a strapping cycle including: (1) a tensioning cycle during which the strapping tool tensions strap (metal strap in this example embodiment) around a load; and (2) a sealing cycle during which the strapping tool, after tensioning the strap, attaches overlapping portions of the strap to one another by cutting notches into a seal element positioned around the overlapping portions of the strap and into the overlapping portions of the strap themselves (referred to as “notching” in the strapping industry and in this Detailed Description) and cuts the strap from the strap supply. 
     The strapping tool  50  includes a housing  100 , a working assembly  200 , first and second handles  1100  and  1200 , a display assembly  1300 , an actuating assembly  1400 , a power supply  1500 , a controller  1600  ( FIG.  1 B ), one or more sensors  1700  ( FIG.  1 B ), a retaining assembly  1800  ( FIGS.  8 A- 9 B ), and a retainer-activation assembly  3850  ( FIGS.  10 - 14   ). 
     The housing  100 , which is best shown in  FIG.  1 A , is formed from multiple components (not individually labeled) that collectively at least partially enclose and/or support some (or all) of the other assemblies and components of the strapping tool  50 . The housing also supports the retaining assembly  1800  and the retainer-activation assembly  3850 , as explained below with reference to  FIGS.  8 A- 14   . In this example embodiment, the housing  100  includes a front housing section that at least partially encloses and/or supports at least some of the components of the working assembly  200 , the display assembly  1300 , and the actuating assembly  1400 ; a rear housing section that at least partially encloses and/or supports the power supply  1500  and the controller  1600 ; and a connector housing section that extends between and connects the bottoms of the front and rear housing sections. The first handle  1100  extends between the tops of the front and rear housing sections, and in some embodiments is integrally formed with the housing sections. This is merely one example, and in other embodiments the components of the strapping tool may be supported and/or enclosed by any suitable portion of the housing  100 . The housing  100  may be formed from any suitable quantity of components joined together in any suitable manner. In this example embodiment, the housing  100  is formed from plastic, though it may be made from any other suitable material in other embodiments. 
     The working assembly  200  includes the majority of the components of the strapping tool  50  that are configured to carry out the strapping cycle to tension the strap around the load, attach the overlapping portions of the strap to one another, and cut the strap from the strap supply. Specifically, the working assembly  200  includes a support  300 , a tensioning assembly  400 , a sealing assembly  500 , a drive assembly  700 , a rocker-lever assembly  900 , a gate assembly  1000 , and a decoupling assembly  1900 . 
     The support  300 , which is best shown in  FIG.  2   , serves as a direct or indirect common mount for the tensioning assembly  400 , the sealing assembly  500 , the drive assembly  700 , the rocker-lever assembly  900 , the gate assembly  1000 , and the decoupling assembly  1900 . The support  300  also includes components configured to help change the effective length of a linkage  820  of the conversion assembly  800  of the drive assembly  700  during the sealing cycle, as explained below with respect to  FIGS.  24 A- 26 H . 
     The support  300  includes a body  310 , a foot  320  extending transversely from a bottom of the body  310 , a tensioning-assembly-mounting element  330  extending rearward from the body  310 , and a drive-and-conversion-assembly-mounting element  340  extending upwardly from the body  310 . A front side of the body  310  defines a gate-receiving recess  350  sized, shaped, oriented, and otherwise configured to receive a gate  1010  of the gate assembly  1000  and to enable the gate  1010  to move between a lower home position and an upper strap-insertion position (described below with respect to  FIGS.  8 A- 9 B ). The body  310  includes aligned first and second sealing-assembly-mounting tongues  372   a  and  372   b  on one side of the gate-receiving recess  350  and aligned third and fourth sealing-assembly-mounting tongues  374   a  and  374   b  on the other side of the gate-receiving recess  350 . Circumferentially spaced first and second linkage engagers  392  and  394  project from the drive-and-conversion-assembly-mounting element  340 . A roller  380  is coupled to and freely rotatable relative to the foot  320 . 
     The tensioning assembly  400 , which is best shown in  FIGS.  4 A- 4 D , is configured to tension the strap around the load during the tensioning cycle. The tensioning assembly  400  includes a tensioning-assembly support  410 , tensioning-assembly gearing  420 , a tension wheel  440  driven by the tensioning-assembly gearing  420 , and covers (not labeled) mounted to the tensioning-assembly support  410  to partially or completely enclose certain components of the tensioning-assembly gearing  420  and the tension wheel  440 . 
     The tensioning-assembly gearing  420  includes: a driven gear  421 ; a first sun gear  422 ; first planet gears  423   a ,  423   b , and  423   c ; a carrier  424 ; a first ring gear  425 ; a spacer  426 ; a second ring gear  427 ; a tension-wheel mount  428 ; and second planet gears  429   a ,  429   b , and  429   c . The components of the tensioning-assembly gearing  420  are centered on—and certain of them are rotatable about—a tension-wheel rotational axis  440   a . The carrier  424  includes a first planet-gear carrier  424   a  to which the first planet gears  423   a - 423   c  are rotatably mounted (such as via respective bearings and mounting pins) and a second sun gear  424   b  rotatable with (and here integrally formed with) the planet-gear carrier  424   a  about the tension-wheel rotational axis  440   a . The first ring gear  425  includes internal teeth  425   it  and external teeth  425   ot . The second ring gear  427  includes internal teeth  427   it . The tension-wheel mount  428  includes a second planet-gear carrier  428   a  and a tension-wheel shaft  428   b  rotatable with (and here integrally formed with) the second planet-gear carrier  428   a  about the tension-wheel rotational axis  440   a . The second planet gears  429   a - 429   c  are rotatably mounted to the second planet-gear carrier  428   a  (such as via respective bearings and mounting pins). 
     The first sun gear  422  is fixedly mounted to the driven gear  421  (such as via a splined connection) such that the driven gear and the first sun gear rotate together about the tension-wheel rotational axis  440   a . The first sun gear  422  meshes with and drivingly engages the first planet gears  423   a - 423   c . The first planet gears mesh with the internal teeth  425   it  of the first ring gear  425 . The second planet gears mesh with the internal teeth  427   it  of the second ring gear  427 . The spacer  426  separates the first and second ring gears  425  and  427 . The second sun gear  424   b  extends through the spacer  426  and meshes with and drivingly engages the second planet gears  429   a - 429   c . The tension wheel  440  is fixedly mounted to the tension-wheel shaft  428   b  (such as via a splined connection) such that the tension-wheel shaft and the tension wheel rotate together about the tension-wheel rotational axis  440   a.    
     The tensioning-assembly gearing  420  is mounted to the tensioning-assembly support  410 . The second ring gear  427  is fixed in rotation about the tension-wheel rotational axis  440   a  relative to the tensioning-assembly support  410  (that is, the second ring gear  427  is not rotatable about the tension-wheel rotational axis  440   a  relative to the tensioning-assembly support  410 ). In this example embodiment, pins (which are shown but not labeled) are positioned between the outer surface of the second ring gear  427  and the tensioning-assembly support  410  to prevent relative rotation, though any suitable components (such as set screws, glue, or high-friction components or fasteners) may be used to do so. The decoupling assembly  1900  (except when actuated, as described below) fixes the first ring gear  425  in rotation about the tension-wheel rotational axis  440   a  relative to the tensioning-assembly support  410  (so the first ring gear cannot rotate about the tension-wheel rotational axis  440   a  relative to the tensioning-assembly support  410 ). 
     During the tensioning cycle, the drive assembly  700  drives the driven gear  421 , as described below. The driven gear  421  begins rotating itself and the first sun gear  422  about the tension-wheel rotational axis  440   a  in a tensioning rotational direction (clockwise from the perspective of  FIG.  4 B  in this example embodiment). The first sun gear  422  drives the first set of planet gears  423   a - 423   c . Since the decoupling assembly  1900  prevents the first ring gear  425  from rotating about the tension-wheel rotational axis  440   a , rotation of the planet gears  423   a - 423   c  causes the carrier  424 —including the second sun gear  424   b —to rotate about the tension-wheel rotational axis  440   a  in the tensioning rotational direction. the second sun gear  424   b  drives the second set of planet gears  429   a - 429   c . Since the second ring gear  427  cannot rotate about the tension-wheel rotational axis  440   a , rotation of the planet gears  429   a - 429   c  causes the tension-wheel mount  428  and the tension wheel  440  mounted thereto to rotate about the tension-wheel rotational axis  440   a  in the tensioning rotational direction. Accordingly, the tensioning-assembly gearing  420  operatively connects the drive assembly  700  to the tension wheel  440  to rotate the tension wheel  440  about the tension-wheel rotational axis  440   a  in the tensioning rotational direction. 
     The tensioning assembly  400  is movably mounted to the tensioning-assembly-mounting element  330  of the support  300  and configured to pivot relative to the support  300 —and particularly relative to the foot  320  of the support  300 —under control of the rocker-lever assembly  900  (as described below) and about a tensioning-assembly-pivot axis  405   a  of a tensioning-assembly-pivot shaft  405  between a strap-tensioning position ( FIGS.  7 A,  8 A , and  8 B) and a strap-insertion position ( FIGS.  7 C,  9 A, and  9 B ). When the tensioning assembly  400  is in the strap-tensioning position, the tension wheel  440  is adjacent to (and in this embodiment contacts) the roller  380  of the support  300  (or the upper surface of the strap if the strap has been inserted into the strapping tool  50 ). When the tensioning assembly  400  is in the strap-insertion position, the tension wheel  440  is spaced-apart from the roller  380  to enable the top portion of the strap (described below) to be inserted between the tension wheel  440  and the roller  380 . A tensioning-assembly-biasing element  400   s  ( FIG.  3 B ), which is a compression spring in this example embodiment but may be any other suitable type of biasing element, biases the tensioning assembly  400  to the strap-tensioning position. 
     The decoupling assembly  1900 , which is best shown in  FIGS.  5 A- 5 D , is configured to enable the tension wheel  440  to rotate about the tension-wheel rotational axis  440   a  in a direction opposite the tensioning rotational direction to facilitate removal of the tool  50  from the strap after the tensioning process is complete. The decoupling assembly  1900  includes a decoupling-assembly shaft  1910 , a decoupling-assembly housing  1920 , a first engageable element  1930 , an expandable element  1940 , a second engageable element  1950 , and first and second bearings  1960   a  and  1960   b.    
     The decoupling-assembly shaft  1910  includes a body  1912  having a first end  1912   a  having an irregular cross-section and second end  1912   b  having teeth. A first bearing support  1914  extends from the first end  1912   a , and a second bearing support  1916  extends from the second end  1912   b . The decoupling-assembly housing  1920  includes a tubular body  1922  having teeth  1924  extending around its outer circumference. The body  1922  defines an opening  1922   o . The first engageable element  1920  comprises a tubular bushing having a cylindrical outer surface and an interior surface having a perimeter that matches the perimeter of the first end  1912   a  of the body  1912  of the decoupling-assembly shaft  1910 . The expandable element  1940  includes a torsion spring having a first end  1940   a  and a second end  1940   b . The second engageable element  1950  includes a tubular body  1952  and an annular flange  1954  at one end of the body  1952 . An opening  1954   o  is defined through the flange  1954 . 
     The first engageable element  1930  is mounted on the first end  1912   a  of the body  1912  of the decoupling-assembly shaft  1910  for rotation therewith and is disposed within the body  1922  of the decoupling-assembly housing  1920 . The second engageable element  1950  is also disposed within the body  1922  of the decoupling-assembly housing  1920  such that the body  1952  of the second engageable element  1950  is adjacent the first engageable element  1930  and such that at least part of the decoupling-assembly shaft  1910  extends through the second engageable element  1950 . The expandable element  1940 , which is a torsion spring in this example embodiment, is disposed within the body  1922  of the decoupling assembly housing  1920  and circumscribes the first engageable element  1930  and the body  1952  of the second engageable element  1950 . The outer diameters of the first engageable element  1930  and the body  1952  of the second engageable element are substantially the same and are equal to or larger than the resting inner diameter of the torsion spring  1940 . This means that the torsion spring  1940  exerts a compression force on the first engageable element  1930  and the body  1952  of the second engageable element that prevents those components (and the decoupling-assembly shaft  1910 ) from rotating relative to one another. The first end  1940   a  of the expandable element  1940  is received in the opening  1954   o  defined through the flange  1954  of the second engageable element  1950 , and the second end  1940   b  of the expandable element  1940  is received in the opening  1922   o  defined in the body  1922  of the decoupling-assembly housing  1920 . The bearings  1960   a  and  1960   b  are mounted on the first and second bearing supports  1914  and  1916 , respectively, of the decoupling-assembly shaft  1910 . 
     As best shown in  FIGS.  3 B,  5 D, and  6 A , the decoupling assembly  1900  is mounted to the tensioning-assembly support  410  and operatively connected to the tensioning-assembly gearing  420 . More specifically, the decoupling assembly  1900  is mounted to the tensioning-assembly support  410  via a fastener (not labeled) that fixes the second engageable element  1950  in rotation relative to the tensioning-assembly support  410  such that the second engageable element  1950 —and the first end  1940   a  of the expandable element  1940  received in the opening  1954   o  of the flange  1954  of the second engageable element  1950 —cannot rotate relative to the tensioning-assembly support  410 . The teeth on the second end  1912   b  of the body  1912  of the decoupling-assembly shaft  1910  mesh with the outer teeth  425   ot  of the first ring gear  425  of the tensioning-assembly gearing  420  of the tensioning assembly  400 . Since the body  1952  is fixed in rotation relative to the tensioning-assembly support  410  and the decoupling-assembly shaft  1910  is fixed in rotation with the first engageable element  1930 , the decoupling-assembly shaft  1910  is fixed in rotation relative to the tensioning-assembly housing  410 . Since the teeth on the second end  1912   b  engage the outer teeth  425   ot  of the first ring gear  425  of the tensioning-assembly gearing  420 , the decoupling assembly  1900  prevents the first ring gear  425  from rotating about the tension-wheel rotational axis  440   a.    
     The decoupling assembly  1900  is actuatable (such as by the rocker-lever assembly  900  as described below) to eliminate the connection between the torsion spring  1940  and the first engageable element  1930  such that the first engageable element  1930  and the decoupling-assembly shaft  1910  may rotate relative to the second engageable element  1930 . As explained above, the second engageable element  1950  and the first end  1940   a  of the expandable element  1940  (that is received in the opening  1954   o  of the flange  1954  of the second engageable element  1950 ) are fixed in rotation relative to the tensioning-assembly support  410 . To eliminate the connection between the torsion spring  1940  and the first engageable element  1930 , the decoupling-assembly housing  1920  is rotated relative to the tensioning-assembly support  410 , the first end  1940   a  of the torsion spring  1940 , and the second engageable element  1950 . The second end  1940   b  of the torsion spring  1940 , which is received in the opening  1922   o  defined in the body  1922  of the decoupling-assembly housing  1920 , rotates with the decoupling-assembly housing  1920 . As this occurs, the inner diameter of the torsion spring  1940  near its second end  1940   b  begins expanding, and eventually expands enough (thereby reducing the compression force or eliminating it altogether) to enable the first engageable element  1930  and the decoupling-assembly shaft  1910  to rotate relative to the second engageable element  1950  (and the torsion spring  1940 ). 
     Upon completion of the tensioning cycle, the tension wheel  440  holds a significant amount of tension in the strap, and the strap exerts a counteracting force (or torque) on the tension wheel  440  in a direction opposite the tensioning direction. Actuation of the decoupling assembly  1900  after the tensioning process is completed enables the tension wheel  440  to rotate in the direction opposite the tensioning direction to release that tension in a controlled manner. Specifically, upon completion of the tensioning cycle, the decoupling-assembly shaft  1910  continues to prevent the first ring gear  425  of the tensioning-assembly gearing  420  from rotating about the tension-wheel rotational axis  440 , which prevents the tension wheel  440  from rotating in the direction opposite the tensioning direction. As the decoupling-assembly housing  1920  is rotated (such as via actuation of the rocker-lever assembly  900  as described below), the inner diameter of the torsion spring  1940  near its second end  1940   b  begins expanding. Eventually, the force the first ring gear  425  exerts on the decoupling-assembly shaft  1910  exceeds the compression force the torsion spring  1940  exerts on the first engageable element  1930 . When this occurs, the first ring gear  425  rotates in the direction opposite the tensioning direction about the tension-wheel rotational axis  440   a . Since the first sun gear  422  is fixed in rotation (by the drive assembly  700 ), this causes the first planetary gears  423   a - 423   c  to rotate in the direction opposite the tensioning direction about the tension-wheel rotational axis  440   a . This (as explained above) causes the tension wheel  440  to rotate in the direction opposite the tensioning direction about the tension-wheel rotational axis  440   a.    
     The rocker-lever assembly  900 , which is best shown in  FIGS.  6 A- 6 E , is operably connected to: (1) the tensioning assembly  400  and configured to move the tensioning assembly  400  relative to the support  300  from the strap-tensioning position to the strap-insertion position; and (2) the decoupling assembly  1900  and configured to actuate the decoupling assembly, thereby enabling the tension wheel  440  to rotate in the direction opposite the tensioning rotational direction. The rocker-lever assembly  900  includes a rocker lever  910 , a rocker-lever gear  930 , a rocker-lever pivot pin  940 , a rocker-lever travel pin  950 , and a rocker-lever biasing element (not shown). The rocker lever  910  includes a rocker-lever body  912  defining two aligned travel-pin slots  912   s , a rocker-lever arm  914  extending rearwardly from the rocker-lever body  912 , and a blocking finger  916  extending upwardly from the rocker-lever body  912  and transverse to the rocker-lever arm  914 . 
     The rocker-lever pivot pin  940  and the rocker-lever travel pin  950  attach the rocker lever  910  to the tensioning assembly  400  such that the rocker lever  910  is pivotable relative to the tensioning assembly  400  between a home position ( FIG.  7 A ) and an intermediate position ( FIG.  7 B ). Specifically, the rocker-lever pivot pin  940  extends through openings (not shown) defined through the tensioning-assembly support  410  and the rocker-lever body  912  of the rocker lever  910  such that the rocker lever  910  is pivotable about the pivot pin  940 —which defines a rocker-lever pivot axis (not shown)—and relative to the tensioning assembly  400  and the decoupling assembly  1900 . The rocker-lever travel pin  950  extends through an opening (not shown) defined through the tensioning-assembly support  410  and through the travel-pin slots  912   s  of the rocker-lever body  912 . 
     As the rocker lever  910  pivots about the pivot pin  940  (and the rocker-lever pivot axis) and relative to the tensioning assembly  400  and the support  300 , the travel-pin slots  912   s  move relative to the rocker-lever travel pin  950  (which is mounted to the tensioning-assembly support  410 ). The size, shape, position, and orientation of the travel-pin slots  912   s  constrain the pivoting movement of the rocker lever  910  about the pivot pin  940  between the home and intermediate positions. As shown in  FIG.  7 A , when the rocker lever  910  is in its home position, the rocker-lever travel pin  950  is positioned at and engages the upper ends (not labeled) of the travel-pin slots  912   s , preventing the rocker lever  910  from further rotation relative to the tensioning assembly  400  in the clockwise direction. Conversely, and as shown in  FIG.  7 B , when the rocker lever  910  is in its intermediate position, the rocker-lever travel pin  950  is positioned at the lower ends (not labeled) of the travel-pin slots  912   s , preventing the rocker lever  910  from further rotation relative to the tensioning assembly  400  in the counter-clockwise direction. Although not shown here, the rocker-lever biasing element, which is a torsion spring in this example embodiment but may be any other suitable component, biases the rocker lever  910  to its home position. 
     As best shown in  FIG.  6 A , the rocker-lever gear  930  is attached to the rocker-lever body  912  of the rocker lever  910  via the rocker-lever travel pin  950  such that the rocker-lever gear  930  is rotatable about the rocker-lever travel pin  950 . The rocker lever  910  is operably connected to the rocker-lever gear  930  and configured to rotate the rocker-lever gear  930  about the rocker-lever travel pin  950  as the rocker lever  910  pivots from its home position to its intermediate position. As the rocker-lever gear  930  rotates, it actuates the decoupling assembly  1900 , as described above. More specifically, as the rocker-lever gear  930  rotates, it meshes with the teeth  1924  of the body  1922  of the decoupling-assembly housing  1920 , thereby forcing the decoupling-assembly housing  1920  to rotate (thereby actuating the decoupling assembly  1900 ). 
     As explained above and as shown in  FIG.  7 B , once the rocker lever  910  reaches its intermediate position, the rocker-lever travel pin  950  is positioned at the lower ends of the travel pin slots  912   s , preventing the rocker lever  910  from further rotation relative to the tensioning assembly  400  in the counter-clockwise direction. At this point, if the tensioning assembly  400  is in its strap-tensioning position, as shown in  FIG.  7 B , continued application of force on the rocker lever  910  (and particularly the rocker-lever arm  914 ) towards the handle  1100  causes the rocker lever  910  and the tensioning assembly  400  to rotate together about the tensioning-assembly-pivot axis  405   a  until the rocker lever  910  reaches its actuated position and the tensioning assembly  400  reaches its strap-insertion position.  FIG.  7 C  shows the rocker lever  910  in its actuated position and the tensioning assembly  400  in its strap-insertion position. 
     The blocking finger  916  is sized, shaped, positioned, oriented, and otherwise configured such that, when the rocker lever  910  is in its home position and the tensioning assembly  400  is in its strap-tensioning position, the blocking finger  916  prevents the tensioning assembly  400  from moving from its strap-tensioning position to its strap-insertion position (and the resultant movement of the rocker lever  910  towards the handle  1100 ). As best shown in  FIGS.  7 A- 7 D , the housing  100  defines a blocking finger opening  980  sized and shaped to enable the blocking finger  916  to pass through the opening  980  and into the housing  100  as the rocker lever  910  pivots from its home position to its intermediate position. 
     When the tensioning assembly  400  is in its strap-tensioning position and the rocker lever  910  is in its home position, as shown in  FIG.  7 A , the blocking finger  916  is adjacent a portion of the housing  100  that defines the blocking finger opening  980  (though it may be adjacent any other suitable portion of the housing or other component of the tool used for this purpose). If at this point a force acts on the tensioning assembly  400  (such as the force caused by cutting the strap from the strap supply and releasing the stored tension therein) and attempts to move the tensioning assembly  400  from its strap-tensioning position to its strap-insertion position, the resultant upward movement of the rocker lever  910 —without pivoting away from its home position relative to the tensioning assembly  400 —results in the blocking finger  916  engaging the housing  100 . As shown in  FIG.  7 D , this prevents further movement of the tensioning assembly  400  toward its strap-insertion position and prevents further movement of the rocker lever  910  toward the handle  1100 . 
     The blocking finger  916  does not prevent the tensioning assembly  400  from moving from its strap-tensioning position to its strap-insertion position when the rocker lever  910  is in its intermediate position and the tensioning assembly  400  is in its strap-tensioning position. As shown in  FIG.  7 B , the blocking finger  916  passes through the blocking finger opening  980  and into the housing as the rocker lever  910  moves from its home position to its intermediate position. As shown in  FIG.  7 C , as the operator keeps moving the rocker lever  910  to its actuated position, the blocking finger  916  does not prevent the tensioning assembly  400  from pivoting upwards about the tensioning-assembly-pivot axis  405   a  to its strap-insertion position. Accordingly, for the rocker lever  910  to move the tensioning assembly  400  from its strap-tensioning position to its strap-insertion position, the rocker lever  910  must first be moved from its home position to its intermediate position while the tensioning assembly  400  is in its strap-tensioning position (best shown in  FIG.  7 B ). 
     The retaining assembly  1800 , which is best shown in  FIGS.  8 A- 9 B , is mounted to the housing  100  and configured to retain the tensioning assembly  400  in its strap-insertion position and, responsive to initiation of the tensioning cycle, to automatically release the tensioning assembly  400  and enable the tensioning assembly  400  to move (via the tensioning-assembly-biasing element) to its strap-tensioning position. The retaining assembly  1800  includes a retainer  1810 , a retainer mount  1820 , and a retainer biasing element  1830 . 
     The retainer  1810  includes a body  1812  with a mounting ear  1814  at one end, a tension-wheel-shaft engager  1816  at the opposite end, and a biasing-element engager  1818  projecting from the body  1812  between the mounting ear  1814  and the tension-wheel-shaft engager  1816 . The retainer mount  1820  includes a mounting pin attached to and projecting inward from the housing  100 . The retainer  1810  is mounted to the retainer mount  1820  via the mounting ear  1814  so the retainer  1810  is rotatable about the retainer mount  1820  and relative to the tension-wheel shaft  428   b  (and here the entire tensioning assembly  400 ) between a release position ( FIGS.  8 A and  8 B ) and a retaining position ( FIGS.  9 A and  9 B ). The retainer biasing element  1830  (here, a torsion spring though it may include any suitable spring or other type of biasing element) exerts a force on the biasing-element engager  1818  that biases the retainer  1810  toward its retaining position. 
     As shown in  FIGS.  8 A and  8 B , when the tensioning assembly  400  is in its strap-tensioning position, the retainer  1810  is in its release position. When the retainer  1810  is in its release position, the retainer biasing element  1830  forces the tension-wheel-shaft engager  1816  into contact with the tension-wheel shaft  428   b . This force is low enough (e.g., the spring constant is sufficiently low and the coefficient of friction between the tension-wheel shaft and the tension-wheel-shaft engager is sufficiently low) so as not to affect the ability of the tension-wheel shaft  428   b  to rotate during the tensioning cycle. As the operator moves the rocker lever  910  from its home position to its actuated position (such as to release strap from the strapping tool  50 ), the tensioning assembly  400  begins rotating to its strap-insertion position. As the tensioning assembly  400  reaches its strap-insertion position, the tension-wheel shaft  428   b  ascends above the tension-wheel-shaft engager  1816 . When this occurs, the retainer biasing element  1830  forces the retainer  1810 , which at this point is no longer blocked by the tension-wheel shaft  428   b , to rotate to its retaining position. When the retainer  1810  is in its retaining position, the retainer biasing element  1830  forces the body  1812  into contact with the tension-wheel shaft  428   b.    
     At this point, as shown in  FIGS.  9 A and  9 B , the tension-wheel-shaft engager  1816  is beneath (between the tension-wheel shaft  428   b  and the foot  320  of the support  300 ) and engages the underside of the tension-wheel shaft  428   b . When the operator releases the rocker lever  910 , the tension-wheel-shaft engager  1816  prevents the tensioning assembly  400  from moving to its strap-tensioning position. The tensioning-assembly-biasing element  400   s  causes the tension-wheel shaft  428   b  to impose a force on the tension-wheel-shaft engager  1816 . This force is large enough to prevent the tension-wheel-shaft engager  1816  from moving to its release position as the strapping tool  50  is moved around. Additionally, the force the retainer-biasing element  1830  continues to exert on the retainer  1810  acts to resist against the retainer  1810  moving to its release position. Upon initiation of the tensioning cycle, the tension-wheel shaft  428   b  begins rotating (counter-clockwise from the viewpoint shown in  FIGS.  9 A and  9 B ). The coefficient of friction between the tension-wheel shaft  428   b  and the retainer  1810  is sufficiently high and the force the retainer biasing element  1830  exerts on the retainer  1810  is sufficiently low so that the rotation of the tension-wheel shaft  428   b  forces the retainer  1810  to rotate to its release position. As this occurs, the tensioning-assembly-biasing element forces the tensioning assembly  400  to its strap-tensioning position, at which point the tensioning assembly  400  begins tensioning the strap. 
     The ability of the retaining assembly to retain the tensioning assembly in its strap-insertion position reduces operator fatigue by: (1) eliminating the requirement for the operator to continuously hold the rocker lever against the force of the tensioning-assembly-biasing element in its actuated position while removing the strap from the strapping tool; and (2) eliminating the requirement for the operator to, when ready to insert another strap into the strapping tool for tensioning, pull the rocker lever and continuously hold it against the force of the tensioning-assembly-biasing element in its actuated position while inserting the strap into the strapping tool. 
     The retainer-activation assembly  3850 , which is best shown in  FIGS.  10 - 14   , is configured to enable an operator of the strapping tool  50  to activate or deactivate the ability of the retaining assembly  1800  to retain the tensioning assembly  400  in its strap-insertion position. The retainer-activation assembly  3850  includes a retainer-activation switch  3852 , a retainer-activation-switch biasing element  3854  (which is a spring in this example embodiment but may be any other suitable biasing element), and first and second biasing-element retainers  3856  and  3858  (which are washers in this example embodiment but may be any other suitable components). The retainer-activation switch  3852  includes a disc-shaped head  3852   a , a shaft  3852   b  extending from and rotatable with the head  3852   a , and a retainer engager  3852   c  (which is a cam in this example embodiment but may be any other suitable component) at the end of the shaft  3852   b  opposite the head  3852   a  and rotatable with the head  3852   a  and the shaft  3852   b . The retainer-activation-switch biasing element  3854  circumscribes the shaft  3852   b  and is positioned between the head  3852   a  and the retainer engager  3852   c . The biasing-element retainers  3856  and  3858  also circumscribe the shaft  3852   b  and are positioned on opposite sides of the retainer-activation-switch biasing element  3854 . 
     The retainer-activation assembly  3850  is mounted to the housing  100  such that the head  3852   a  of the retainer-activation switch  3852  is outside the housing  100 , the shaft  3852   b  of the retainer-activation switch  3852   b  extends through an opening (not labeled) in the housing  100 , and the retainer engager  3852   c  is inside the housing  100  and adjacent the retainer  1810 . The retainer-activation-switch biasing element  3854  is in a compressed state and thus exerts a force against the housing  100  and the retainer engager  3852   c  via the biasing-element retainers  3856  and  3858 . This force acts to resist rotation of the retainer-activation switch  3852 . 
     The retainer-activation assembly  3850  is mounted to the housing  100  such that the retainer-activation switch  3852  is rotatable relative to the housing  100  and the retainer  1810  of the retaining assembly  1800  between a deactivated position and an activated position. As shown in  FIGS.  11  and  12 A , when the retainer-activation switch  3852  is in its deactivated position, the retainer engager  3852   c  is positioned to engage the body  1812  of the retainer  1810  and hold the retainer  1810  in a deactivated position against the biasing force of the retainer biasing element  1830 . In this example embodiment, when the retainer  1810  is in its deactivated position, the retainer  1810  is oriented so the tension-wheel-shaft engager  1816  is disengaged from the tension-wheel shaft  428   b  of the tensioning assembly  400  (though in other embodiments the deactivated position and the release position of the retainer  1810  are the same). By holding the retainer  1810  in the deactivated position, the retainer-activation switch  3852  prevents the retainer biasing element  1830  from rotating the retainer  1810  to its retaining position and into contact with the tension-wheel shaft  428   b  when the operator moves the rocker lever  910  from its home position to its actuated position (such as to release the strap from the strapping tool  50 ). This necessarily prevents the tension-wheel-shaft engager  1816  from engaging the underside of the tension-wheel shaft  428   b  and retaining the tensioning assembly  400  in its strap-insertion position when the operator releases the rocker lever  910 . Accordingly, when the retainer-activation switch  3852  is in its deactivated position, it deactivates the ability of the retaining assembly  1800  to retain the tensioning assembly  400  in its strap-insertion position. 
     As shown in  FIG.  12 B , when the retainer-activation switch  3852  is in its activated position, the retainer engager  3852   c  is disengaged from the body  1812  and positioned to enable the retainer  1810  to rotate between its release and retaining positions and operate as described above with respect to  FIGS.  8 A- 9 B . Thus, when the operator moves the rocker lever  910  from its home position to its actuated position, the retainer biasing element  1830  forces the retainer  1810  to rotate to its retaining position and contact the tension-wheel shaft  428   b . When the operator releases the rocker lever  910 , the tension-wheel-shaft engager  1816  of the retainer  1810  engages the underside of the tension-wheel shaft  428   b  and prevents the tensioning assembly  400  from moving from its strap-insertion position to its strap-tensioning position. Accordingly, when the retainer-activation switch  3852  is in its activated position, it activates the ability of the retaining assembly  1800  to retain the tensioning assembly  400  in its strap-insertion position. 
     The retainer-activation assembly  3850  thus provides operators the flexibility to choose whether they want to take advantage of the retaining assembly&#39;s ability to retain the tensioning assembly in its strap-insertion position, which may be desirable in certain use cases and not desirable in others. In certain embodiments, the tool includes the retaining assembly but not the retainer-activation assembly. 
     The gate assembly  1000 , which is best shown in  FIGS.  8 A- 9 B , is configured to facilitate easy insertion of the strap and is adjustable to accommodate straps of differing thicknesses. The gate assembly  1000  includes a gate  1010  and multiple linkages  1012 ,  1014 , and  1016 . 
     The gate  1010  is slidably received in the gate-receiving recess  350  of the body  310  of the support  300  and retained in that recess via a retaining bracket (not shown for clarity). A strap-receiving opening (not labeled) is defined between the bottom of the gate  1010  and the top surface of the foot  320  of the support  300 . The gate  1010  is movable relative to the support  300  between a home position ( FIGS.  8 A and  8 B ) and a retracted position ( FIGS.  9 A and  9 B ). When in the home position, the gate  1010  is positioned relative to the foot  320  so the height H 1  of the strap-receiving opening is equal to or just larger than the thickness of the particular strap to-be-tensioned and sealed. When in the retracted position, the gate  1010  is positioned relative to the foot  320  so the height H 2  of the strap-receiving opening is larger than the height H 1 . 
     The position of the tensioning assembly  400  controls the position of the gate  1010  via the linkages  1012 ,  1014 , and  1016 . The linkage  1016  is fixedly connected at one end to the tensioning assembly  400  and pivotably connected at the other end to one end of the linkage  1014 . The other end of the linkage  1014  is pivotably connected to one end of the linkage  1012 . The other end of the linkage  1012  is fixedly connected to the gate  1010 . The linkages  1012 ,  1014 , and  1016  are sized, shaped, positioned, oriented, and otherwise configured such that: (1) when the tensioning assembly  400  is in the strap-tensioning position, the gate  1010  is in its home position (and the strap-receiving opening has the height H 1 ); and (2) when the tensioning assembly  400  is in its strap-insertion position, the gate  1010  is in its retracted position (and the strap-receiving opening has the height H 2 ). More specifically, when the tensioning assembly  400  is pivoted from the strap-tensioning position to the strap-insertion position, the linkage  1016  is pivoted counter-clockwise (from the viewpoint shown in  FIGS.  8 A- 9 B ). This causes the linkage  1014  to pivot clockwise, which forces the linkage  1012  to move upward and carry the gate  1010  with it. 
     One issue with certain known strapping tools is that it is difficult to insert the strap into the strapping tools. These known strapping tools include a gate positioned forward of the tension wheel so the seal engages the gate during the tensioning cycle and so the gate prevents the seal from contacting the tension wheel. The gate is fixed in place and positioned so the strap-receiving opening defined between the bottom of the gate the top of the foot of the strapping tool (on which the strap is positioned during operation) has the same height as or a height slightly larger than the thickness of the strap. This prevents the strap from moving up and down during operation of the strapping tool. The problem is that it is difficult and time-consuming for operators to align the strap with the strap-receiving opening to insert the strap into the strap-receiving opening that has a height that at best is slightly larger than the strap is thick. 
     The gate assembly of the present disclosure solves this problem by increasing the height of the strap-receiving opening when the tensioning assembly is moved to its strap-insertion position. In other words, the tensioning assembly is coupled to the gate (via the linkages) so movement of the tensioning assembly from the strap-tensioning position to the strap-insertion position causes the gate to move from its home position to its retracted position to enlarge the strap-receiving opening. This makes it easier for the operator to insert the strap into the strap-receiving opening, which streamlines operation of the strapping tool. 
     The position of the gate  1010  relative to the foot  320  is also variable. Specifically, the gate  1010  can be fixed to the linkage  1012  in any of several different vertical positions. By changing the vertical position of the gate  1010  relative to the linkage  1012 , the operator can vary the height H 1  of the strap-receiving opening when the gate  1010  is in the home position. For instance, in this embodiment, the linkage  1012  is connected to the gate  1010  via a screw. The screw extends through an elongated slot that extends along the length of the gate  1010 . To change the height H 1  of the strap-receiving opening when the gate  1010  is in its home position, the operator loosens the screw, slides the gate  1010  up or down relative to the linkage  1012  (taking advantage of the slot), and re-tightens the screw. 
     One issue with certain known strapping tools is that it is time-consuming to reconfigure the strapping tools for use with straps of different thicknesses. To reconfigure a strapping tool for use with a strap having a different thickness, the operator must replace the existing gate with another gate sized for use with the new strap (e.g., a gate that is longer (for thinner strap) or shorter (for thicker strap)). This requires the operator to partially disassemble the strapping tool, which not only causes downtime but also requires operators to keep the different gates on hand, recognize when a different gate is needed, and properly match the gates to the different strap thicknesses. Using the incorrect gate could result in a failed or suboptimal strapping operation (and in the latter case, suboptimal joint strength). 
     The gate assembly  1000  of the present disclosure solves this problem by enabling the operator to vary the position of the gate  1010  relative to the linkage  1012  and therefore the height H 1  of the strap-receiving opening when the gate  1010  is in its home position. This improves upon prior art strapping tools by enabling the operator to quickly and easily move the gate to accommodate straps of different thicknesses without having to swap out one gate for another. 
     The sealing assembly  500 , which is best shown in  FIGS.  15 A- 20 C , is configured to attach overlapping portions of the strap to one another to form a tensioned strap loop around the load during the sealing cycle by notching both a seal element positioned around the overlapping portions of the strap and the overlapping portions of the strap themselves. The sealing assembly  500  includes a front cover  502 , a back cover  506 , a jaw assembly  520 , an object-blocking assembly  600 , and an object-blocker-lift element  630 . 
     The front cover  502  is generally U-shaped. The back cover  506  includes a generally planar base  506   a , two mounting wings  506   b  and  506   c  extending rearward and inward from opposing lateral ends of the base  506   a , and a lip  506   d  extending forward from the base  506   a  toward the jaw assembly  520 . The object-blocker-lift element  630  is pivotably mounted to the base  506   a  via a pivot pin  640  and configured to rotate about the pivot pin  640 , as described in more detail below in conjunction with the object-blocking assembly  600 . The front cover  502  and the back cover  506  are connected to one another via one or more suitable fasteners (not labeled) and cooperate to partially enclose the jaw assembly  520 , the object-blocking assembly  600 , and the object-blocker-lift element  630 . 
     The sealing assembly  500  is movably (and more particularly, slidably) mounted to the support  300  via the back cover  506 . Specifically, the back cover  506  is positioned so the first and second sealing-assembly-mounting tongues  372   a  and  372   b  of the support  300  are received in a groove defined between the base  506   a  and the first mounting wing  506   b  and so the third and fourth sealing-assembly-mounting tongues  374   a  and  374   b  of the support  300  are received in a groove defined between the base  506   a  and the second mounting wing  506   c . This mounting configuration enables the sealing assembly  500  to move vertically relative to the support  300  and prevents the sealing assembly  500  from moving side-to-side or forward and rearward relative to the support  300 . As best shown in  FIGS.  19 A and  19 B , laterally-spaced-apart first and second sealing-assembly-mounting elements  390   a  and  390   b  are fixedly attached to the body  310  of the support  300  and extend through respective vertically-extending slots (not labeled) defined through the base  506   a  of the back cover  506 . These slots and sealing-assembly-mounting elements  390   a  and  390   b  co-act to constrain the vertical movement of the sealing assembly  500  relative to the support  300  between a (upper) home position ( FIGS.  19 A and  28 A ) at which the sealing-assembly-mounting elements  390   a  and  390   b  are at the lower ends of the slots and a (lower) sealing position ( FIGS.  19 B,  28 B, and  28 C ) at which the sealing-assembly-mounting elements  390   a  and  390   b  are at the upper ends of the slots. As explained below, the drive assembly  700  controls movement of the sealing assembly  500  between its home and sealing positions. 
     As best shown in  FIGS.  15 C and  15 D , the jaw assembly  520  includes a coupler  522 , a coupler pivot  524 , first and second coupler/jaw linkages  526  and  528 , a first jaw  530 , a second jaw  534 , a third jaw  538 , a fourth jaw  542 , a first jaw connector  546 , a second jaw connector  550 , a third jaw connector  566 , a fourth jaw connector  567 , first and second upper jaw pivots  571  and  572 , and first and second lower jaw pivots  573  and  574 . The first and second jaws  530  and  534  form a pair of opposing inner jaws, and the third and fourth jaws  538  and  542  form a pair of opposing outer jaws. 
     The first and second coupler/jaw linkages  526  and  528  are each pivotably connected to the coupler  522  near their respective upper ends via the coupler pivot  524 . This pivotable connection enables the first and second coupler/jaw linkages  526  and  528  to pivot relative to the coupler  522  and the coupler pivot  524  about a longitudinal axis of the coupler pivot  524  (not shown). Here, the coupler pivot  524  includes a pivot pin retained via a retaining ring (not labeled), though it may be any other suitable pivot in other embodiments. As best shown in  FIG.  15 B , the rear end of the coupler pivot  524  is positioned in a slot (not labeled) defined in the back cover  506  so the slot limits the coupler pivot  524  to moving vertically between an upper and a lower position. 
     The respective upper portions of each of the first and second jaws  530  and  534  are pivotably connected to the respective lower ends of the coupler/jaw linkages  526  and  528  via the upper jaw pivots  571  and  572 , respectively. The respective upper portions of each of the third and fourth jaws  538  and  542  are pivotably connected to the respective lower ends of the coupler/jaw linkages  526  and  528  via the upper jaw pivots  571  and  572 , respectively. These pivotable connections enable the first inner and outer jaws  530  and  538  to pivot relative to the coupler/jaw linkage  526  about a longitudinal axis of the upper jaw pivot  571  (not shown) and the second inner and outer jaws  534  and  542  to pivot relative to the coupler/jaw linkage  528  about a longitudinal axis (not shown) of the upper jaw pivot  571 . 
     The respective lower portions of each of the first and second jaws  530  and  534  are pivotably connected by the lower jaw pivots  573  and  574  to the first jaw connector  546 , the second jaw connector  550 , the third jaw connector  566 , and the fourth jaw connector  567 . The respective lower portions of each of the third and fourth jaws  538  and  542  are pivotably connected by the lower jaw pivots  573  and  574  to the first jaw connector  546 , the second jaw connector  550 , the third jaw connector  566 , and the fourth jaw connector  567 . The pivotable connections enable the first and third jaws  530  and  538  to pivot relative to the jaw connectors  546 ,  550 ,  566 , and  567  about a longitudinal axis (not shown) of the lower jaw pivot  573  between respective home positions ( FIG.  28 A ) and sealing positions ( FIG.  28 C ). The pivotable connections enable the second and fourth jaws  534  and  542  to pivot relative to the jaw connectors  546 ,  550 ,  566 , and  567  about a longitudinal axis (not shown) of the lower jaw pivot  574  between respective home positions ( FIG.  28 A ) and sealing positions ( FIG.  28 C ). 
     As best shown in  FIGS.  15 D and  18 C , each jaw has a lower tooth that cuts a notch in the seal element and the overlapping portions of the strap during the sealing cycle and an upper tooth that engages an object blocker  605  of the object-blocking assembly  600  (described below) if the object blocker  605  is in its blocking position (described below) at the start of the sealing cycle and moves the object blocker  605  toward its retracted position as the jaws move to their respective sealing positions. This prevents the jaws from damaging the object blocker  605 . More specifically, the first jaw  530  has a lower tooth  530   a  and an upper tooth  530   b , the second jaw  534  has a lower tooth  534   a  and an upper tooth  534   b , the third jaw  538  has a lower tooth  538   a  and an upper tooth  538   b , and the fourth jaw  542  has a lower tooth  542   a  and an upper tooth  542   b.    
     The object-blocking assembly  600  is mounted to the jaw assembly  520  (and more particularly, to the second jaw connector  550 ) and configured to prevent objects from inadvertently entering the space between the first and second jaws  530  and  534  and the third and fourth jaws  538  and  542 . This space is sometimes referred to herein as the “seal-element-receiving space.” This reduces the possibility of an object interfering with the operation of the strapping tool. This also prevents the jaws of the strapping tool from damaging the object (or vice-versa). As best shown in  FIGS.  16 A and  16 B , the object-blocking assembly  600  includes an object blocker  605  formed from a first object blocker portion  610  and a second object blocker portion  620 ; an object-blocker fastener  650 ; an pin  660 ; multiple biasing elements  670   a ,  670   b ,  670   c , and  670   d ; a biasing-element retainer  680 ; and multiple fasteners  690 . 
     The object blocker  605  is best shown in  FIGS.  17 A and  17 B  and is formed from the first object blocker portion  610  and the second object blocker portion  620  joined by the object-blocker fastener  650  and the pin  660 . The first object blocker portion  610  includes a body  612  and a mating lug  614  extending from a rear surface of the body  612 . The body  612  defines cylindrical biasing-element-receiving bores  612   a  and  612   b  that extend downward from an upper surface of the body  612 . The biasing-element-receiving bores are sized, shaped, oriented, and otherwise configured to partially receive the biasing elements  670   d  and  670   c , respectively. The underside of the body  612  includes a curved object-engaging surface  612   c  (though this surface may be planar in other embodiments). Opposing side surfaces of the body  612  define vertically extending slots  612   d  and  612   e . Tooth-engaging pins  616   a  and  616   b  are received in bores defined in the body  612  from front to back and are positioned to extend across the slots  612   d  and  612   e , respectively. 
     The second object blocker portion  620  includes a body  622  and a mating lug  624  extending from a front surface of the body  622 . The body  622  defines cylindrical biasing-element-receiving bores  622   a  and  622   b  that extend downward from an upper surface of the body  622 . The biasing-element-receiving bores are sized, shaped, oriented, and otherwise configured to partially receive the biasing elements  670   b  and  670   a , respectively. The underside of the body  622  includes a curved object-engaging surface  622   c  (though this surface may be planar in other embodiments). Opposing side surfaces of the body  622  define vertically extending slots  622   d  and  622   e . Tooth-engaging pins  626   a  and  626   b  are received in bores defined in the body  612  from front to back and are positioned to extend across the slots  622   d  and  622   e , respectively. 
     The object blocker  605  is slidably mounted to the second jaw connector  550 . More specifically, as best shown in  FIGS.  16 A and  16 B , the second jaw connector  550  includes a body  552  and a neck  554  extending upward from a center of the body  552 . The body  552  and the neck  554  define an object-blocker-mounting slot  556  therethrough. The object blocker  605  is assembled such that the mounting elements  614  and  624 , the object-blocker fastener  650 , and the pin  660  extend through the object-blocker-mounting slot  556 . After assembly, the object blocker  605  is vertically movable relative to the second jaw connector  550  (and constrained by the size of the object-blocker-mounting slot  556 ) between a (upper) retracted position ( FIG.  19 A ) and a (lower) blocking position ( FIG.  19 B ). The biasing-element retainer  680  is attached to the neck  554  of the second jaw connector  550  via the fasteners  690  to constrain the biasing elements  670   a ,  670   b ,  670   c , and  670   d  in place in their respective biasing-element-receiving bores  622   b ,  622   a ,  612   b , and  612   a  in the object blocker  605 . The biasing elements  670  bias the object blocker  605  to its blocking position. 
     The object-blocker-lift element  630  is operably engageable with the object blocker  605  to maintain the object blocker  605  in its retracted position when the sealing assembly  500  is in its home position to prevent the object blocker  605  from interfering with the seal element and the strap during strap insertion and strap tensioning. In this example embodiment and as best shown in  FIG.  15 C , the object-blocker-lift element  630  includes a body  632  with an object-blocker engager  634  at one end and an opposing free end  636 . As noted above, the object-blocker-lift element  630  is pivotably mounted to the back cover  506  via the pivot pin  640 . The object-blocker-lift element  630  is pivotable relative to the object blocker  605  about a longitudinal axis of the pivot pin  640  (not shown). The object-blocker engager  634  is received in a recess  622   f  ( FIG.  17 B ) that is defined in the second object blocker portion  620  of the object blocker  605  and that is partially defined by an upper wall  622   w  of the second object blocker portion  620 . As best shown in  FIGS.  19 A and  19 B , the free end  636  is positioned between the first sealing-assembly-mounting element  390   a  and the lip  506   d  of the back cover  506 . The object-blocker-lift element  630  is pivotable relative to the remainder of the sealing assembly  500  between a home position ( FIG.  19 B ) and a lifting position ( FIG.  19 A ). 
     The object-blocker-lift element  630  is positioned and configured such that the position of the object-blocker-lift element  630  in part controls the position of the object blocker  605 . Specifically, when the object-blocker-lift element  630  is in the lifting position, the object-blocker-lift element  630  imparts a force on the object blocker  605  that overcomes the biasing force of the biasing elements  670  and maintains the object blocker  605  in its retracted position. Specifically, a surface  634   a  of the object-blocker engager  634  imparts the force on the upper wall  622   w  of the second object blocker portion  620 . Conversely, when the object-blocker-lift element  630  is in its home position, it does not impart this force on the object blocker  605 , and the object blocker  605  can move between its retracted and blocking positions. The biasing elements  670  bias the object-blocker-lift element  630  to its home position (i.e., in this embodiment, biases the upper wall  622   w  into contact with the surface  634   a ). 
     The position of the sealing assembly  500  controls the position of the object-blocker-lift element  630  (and therefore, in part, the position of the object blocker  605 ). As best shown in  FIG.  19 A , when the sealing assembly  500  is in its home position, the first sealing-assembly-mounting element  390   a  engages the object-blocker-lift element  630  between its free end  636  and the pivot pin  640  and forces the object-blocker-lift element  630  into its lifting position. This in turn (and as explained above) forces the object blocker  605  into its retracted position. As the sealing assembly  500  moves from its home position to its sealing position, space is created between the lip  506   d  and the first sealing-assembly-mounting element  390   a . As this space is created, the biasing elements  670  force the object blocker  605  to move toward its blocking position. This causes the object-blocker-lift element  630  to pivot so it maintains contact with the first sealing-assembly-mounting element  390   a .  FIG.  19 B  shows the object-blocker-lift element  630  and the object blocker  605  after they&#39;ve reached their respective home and blocking positions. 
     When the object blocker  605  is in its blocking position and the jaws  530 ,  534 ,  538 , and  542  are in their home positions, the object blocker  605  and the jaws are in a blocking configuration. When these components are in the blocking configuration, the object blocker  605  occupies most of the seal-element-receiving space (not labeled) defined between the pair of jaws  530  and  538  and the pair of jaws  534  and  542  and below the jaw connectors  546 ,  550 ,  566 , and  567 . As described in detail below, responsive to application of a force sufficient to overcome the biasing force of the biasing elements  670 , the object blocker  605  moves from its blocking position to its retracted position and remains there until the force is removed. When in the retracted position, the object blocker  605  is not positioned in the seal-element-receiving space such that a seal element and strap can be positioned there for sealing. 
     If the sealing cycle (described below) is initiated with the object blocker  605  and the jaws  530 ,  534 ,  538 , and  542  in the blocking configuration, the jaws are configured to move the object blocker  605  toward its retracted position to avoid damaging the jaw assembly  520  or any other component of the strapping tool  50  during the sealing cycle. Specifically, when the object blocker  605  is in its blocking position, the upper teeth  530   b ,  534   b ,  538   b , and  542   b  of the jaws  530 ,  534 ,  538 , and  542  are adjacent to the pins  626   b ,  626   a ,  616   b , and  616   a  of the object blocker  605 , respectively. As the jaws begin pivoting from their respective home positions to their respective sealing positions, the upper teeth engage their respective pins. Continued movement of the jaws to their respective sealing positions causes the upper teeth to apply sufficient force to the pins to overcome the biasing force of the biasing elements  670  and move the object blocker  605  toward its retracted position. As this occurs, the lower teeth enter the slots defined in the sides of the object blocker  605 .  FIG.  18 C  shows the jaws in their sealing positions after having moved the object blocker toward its retracted position. 
     One issue with certain known strapping tools that use jaws to crimp or notch the strap and (if applicable) the seal element is that a foreign object may (inadvertently) enter the space between the jaws instead of or in addition to the strap and (if applicable) the seal element. This is problematic for several reasons. The object may interfere with the operation of the strapping tool and cause the joint formed via the attachment of the overlapped strap portions to one another to have suboptimal strength, which could lead to unexpected joint failure and product loss. Additionally, the object could damage the jaws and/or other components of the sealing assembly during the sealing process, which would require tool repairs and cause downtime. Further, the sealing assembly could damage or destroy the object. 
     The object-blocking assembly of the present disclosure solves this problem by ejecting foreign objects from and by preventing foreign objects from inadvertently entering the seal-element-receiving space between the jaws. Specifically, if a loose foreign object—such as the shaft of a screwdriver—is in the seal-element-receiving space between the jaws as the sealing assembly reaches its sealing position, the object blocker will force that object out of the seal-element-receiving space as the object blocker moves from its retracted position to its blocking position. Once the object blocker reaches its blocking position, minimal space exists between the object blocker and the lower teeth of the jaws, thereby preventing foreign objects from entering the seal-element-receiving space between the jaws. 
     As shown in  FIGS.  20 A- 20 C , the first, second, and third jaw connectors  546 ,  550 , and  566  include respective support surfaces  546   s ,  552   s , and  566   s  configured to support the seal element during the sealing cycle. In this example embodiment, the support surfaces  546   s ,  552   s , and  566   s  are planar and parallel to one another. The support surfaces  546   s ,  552   s , and  566   s  support the seal element during the sealing cycle. In this example embodiment, as best shown in  FIGS.  20 B and  20 C , the support surfaces  546   s  and  566   s  of the first and third jaw connectors  546  and  566  are coplanar while the support surface  552   s  of the second jaw connector  550  is offset below the support surfaces  546   s  and  566   s  by a distance Y. In other words, the support surface  552   s  of the second jaw connector  550  is below the support surfaces  546   s  and  566   s  of the first and third jaw connectors  546  and  566 . The lower support surface of the second jaw connector helps prevent the seal element SE from bending along the longitudinal direction of the strap (into and out of the page from the perspective in  FIGS.  20 B and  20 C ) during completion of the sealing cycle. 
     Although not shown here, a cutter is positioned in and movable within a recess defined in the back cover  506  (best shown in  FIG.  15 B ) and mounted to the coupler pivot  524 . Movement of the coupler pivot  524  downwards causes the coupler pivot  524  to force the cutter downward to cut the strap from the strap supply, and movement of the coupler pivot  524  back upward causes the cutter to move back upward. 
     The drive assembly  700 , which is best shown in  FIGS.  3 B and  21 - 23 B , is operably connected to the tensioning assembly  400  and configured to rotate the tension wheel  440  to tension the strap and is operably connected to the sealing assembly  500  to attach the overlapping portions of the strap to one another. The drive assembly  700  includes a working-assembly actuator  710 , a first transmission  720 , a second transmission  730 , a first belt  740 , a third transmission  750 , a second belt  760 , and a conversion assembly  800 . 
     In this example embodiment, the working-assembly actuator  710  includes a motor (and is referred to herein as the motor  710 ), and particularly a brushless direct-current motor that includes a motor output shaft  712  having a motor-output-shaft rotational axis  712   a  (though the motor  710  may be any other suitable type of motor in other embodiments). The motor  710  is operably connected to (via the motor output shaft  712 ) and configured to drive the first transmission  720 , which (as described below) is configured to selectively transmit the output of the motor  710  to either the tensioning assembly  400  or the sealing assembly  500 . In other embodiments, the strapping tool includes separate tensioning and sealing actuators respectively configured to actuate the tensioning assembly and the sealing assembly rather than a single actuator configured to actuate both. 
     The first transmission  720  includes any suitable gearing and/or other components that are configured to selectively transmit the output of the motor  710  to the second transmission  730  via the first belt  740  and to the third transmission  750  via the second belt  760 . More specifically, the first transmission  720  is configured such that: (1) rotation of the motor output shaft  712  in a first rotational direction causes the first transmission  720  to transmit the output of the motor  710  to the second transmission  730  via the first belt  740  and not to the third transmission  750 ; and (2) rotation of the motor output shaft  712  in a second rotational direction opposite the first rotational direction causes the first transmission  720  to transmit the output of the motor  710  to the third transmission  750  via the second belt  760  and not to the second transmission  730 . Thus, in this embodiment, a single motor (the motor  710 ) is configured to actuate both the tensioning and sealing assemblies  400  and  500 . 
     To accomplish this selective transmission of the motor output, the first transmission  720  includes a first belt pulley (or other suitable component) (not labeled) mounted on a first freewheel (not labeled) that is mounted on the motor output shaft  712  and a second belt pulley (or other suitable component) (not labeled) mounted on a second freewheel (not labeled) that is mounted on the motor output shaft  712 . The first belt pulley is operatively connected (via the first belt  740 ) to the second transmission  730 , and the second belt pulley is operatively connected (via the second belt  760 ) to the third transmission  750 . When the motor output shaft  712  rotates in the first direction: (1) the first freewheel and the first belt pulley rotate with the motor output shaft  712 , thereby transmitting the motor output to the second transmission  730  via the first belt  740 ; and (2) the motor output shaft  712  rotates freely through the second freewheel, which does not rotate the second belt pulley. Conversely, when the motor output shaft  712  rotates in the second direction: (1) the second freewheel and the second belt pulley rotate with the motor output shaft  712 , thereby transmitting the motor output to the third transmission  750  via the second belt  760 ; and (2) the motor output shaft  712  rotates freely through the first freewheel, which does not rotate the first belt pulley. This is merely one example embodiment of the first transmission  720 , and it may include any other suitable components in other embodiments. 
     The second transmission  730  is configured to transmit the output of the first transmission  720  to the tensioning assembly  400  to cause the tension wheel  440  to rotate. More particularly, the second transmission  730  is configured to transmit the output of the first transmission  720  to the tensioning-assembly gearing  420  of the tensioning assembly  400  to rotate the tension-wheel shaft  428   b  and the tension wheel  440  thereon. Accordingly, the motor  710  is operatively coupled to the tension wheel  440  (via the first transmission  720 , the first belt  740 , the second transmission  730 , the tensioning-assembly gearing  420 , and the tension-wheel shaft  428   b ) and configured to rotate the tension wheel  440 . In this example embodiment, the second transmission  730  includes intermediary gearing  732  positioned, oriented, and otherwise configured to engage the driven gear  421  of the tensioning-assembly gearing  420  of the tensioning assembly  400 —regardless of the rotational position of the tensioning assembly  400 —to transmit the output of the motor  710  to the tensioning-assembly gearing  420  to rotate the tension wheel  440 . The intermediary gearing  732  is positioned and otherwise configured to maintain the operative connection between the motor  710  and the tensioning assembly  400  as the tensioning assembly  400  pivots between its strap-tensioning and strap-insertion positions. 
     Specifically, and as best shown in  FIG.  21   , the intermediary gearing  732  includes a first intermediary gear  732   a  and a second intermediary gear  732   b . The first and second intermediary gears  732   a  and  732   b  are rotatably mounted (via bearings or any other suitable components) to the tensioning-assembly-pivot shaft  405  and rotatable about the tensioning-assembly-pivot axis  405   a . That is, the first and second intermediary gears  732   a  and  732   b  rotate around the same axis about which the tensioning assembly  400  pivots between its strap-tensioning and strap-insertion positions. The first and second intermediary gears  732   a  and  732   b  are fixed in rotation relative to one another (such as via a splined or keyed connection) and therefore rotate together about the tensioning-assembly-pivot axis  405   a . The first belt  740  engages the first intermediary gear  732   a  and therefore drives the first and second intermediary gears  732   a  and  732   b  in rotation about the tensioning-assembly-pivot axis  405   a.    
     The intermediary gearing  732  transmits the output of the second transmission  730  to the tensioning assembly  400 . More specifically, the second intermediary gear  732   b  is drivingly engaged to and directly drives the tensioning-assembly gearing  420 —and here, the driven gear  421 —which in turn rotates the gear  421  about the tension-wheel rotational axis  440   a.    
     As shown in  FIGS.  23 A and  23 B , since the intermediary gearing  732  is rotatable about the tensioning-assembly-pivot axis  405   a , a distance Z between the tension-wheel rotational axis  440   a  and the tensioning-assembly-pivot axis  405   a  does not change, within operational tolerances, as the tensioning assembly  400  pivots between its strap-tensioning and strap-insertion positions. For example, the distance Z between the tension-wheel rotational axis  440   a  and the tensioning-assembly-pivot axis  405   a  remains the same or at least substantially the same (e.g., +/−10%) when the tensioning assembly  400  pivots between its strap-tensioning and strap-insertion positions. This ensures that the second intermediary gear  732   b  maintains its driving engagement to the driven gear  421  throughout the entire range of motion of the tensioning assembly  400 , ensuring that the motor  710  does not operatively disconnect from the tensioning assembly  400  as the tensioning assembly  400  pivots. This arrangement improves upon an alternative arrangement (not shown) in which the intermediary gearing is not present and in which the first belt  740  directly drives the driven gear  421  of the tensioning-assembly gearing  420 . In this alternative arrangement, the distance between the tension-wheel rotational axis  440   a  and the motor-output-shaft rotational axis  712   a  would decrease as the tensioning assembly  400  pivots from its strap-tensioning position to its strap-insertion position. This pivoting would create slack in the first belt  740 , which could cause the first belt  740  to slip or completely disengage from the motor output shaft  712  and/or the driven gear  421 , thereby causing the tool to malfunction. 
     The third transmission  750  is configured to transmit the output of the first transmission  720  to the conversion assembly  800 . The third transmission  750  may include any suitable components, such as one or more gears and one or more shafts arranged in any suitable manner. In this example embodiment, the third transmission  750  includes third-transmission gearing  752  that is driven in rotation by the second belt  760  about a third-transmission rotational axis  752   a.    
     As best shown in  FIGS.  21  and  22   , the tensioning assembly  400  and the drive assembly  700  define at least four rotational axes: the motor-output-shaft rotational axis  712   a , the tensioning-assembly-pivot axis  405   a , the tension-wheel rotational axis  440   a , and the third-transmission rotational axis  752   a . In this example embodiment, these four rotational axes are parallel to each other. These axes are oriented as follows from left to right from the perspective shown in  FIG.  22   : the tension-wheel rotational axis  440   a , the motor-output-shaft rotational axis, the tensioning-assembly pivot axis  405   a , and the third-transmission rotational axis  752   a . These axes are oriented as follows from bottom to top from the perspective shown in  FIG.  22   : the tension-wheel rotational axis  440   a , the tensioning-assembly pivot axis  405   a , the motor-output-shaft rotational axis  712   a , and the third-transmission rotational axis  752   a.    
     This arrangement of the rotational axes (and the components that rotate around these axes) enables the motor  710  to directly drive the conversion assembly  800  (via the second belt  760 ) and indirectly drive the tensioning assembly  400  (via the first belt  740  and intermediary gearing  732 ). This arrangement of the rotational axes also ensures that the distance Z between the motor-output-shaft rotational axis  712   a  and the tension-wheel rotational axis  440   a  does not change, within operational tolerances (as described above), when the tensioning assembly  400  pivots about the tensioning-assembly-pivot axis  405   a . This distance Z is shown in  FIG.  23 A  where the tensioning assembly  400  is in its strap-insertion position and in  FIG.  23 B  where the tensioning assembly  400  is in its strap-tensioning position. 
     The conversion assembly  800  is configured to transmit the output of the third transmission  750  to the sealing assembly  500  to carry out the sealing cycle, which includes: moving the sealing assembly from its home position to its sealing position, causing the jaws of the sealing assembly to move from their home positions to their sealing positions to cut notches in the seal element and the strap, causing the jaws to move back to their home positions to release the notched seal element and strap, and moving the sealing assembly back to its home position. In doing so, in this embodiment the conversion assembly  800  is configured to convert rotational motion (the rotation of shafts and gears) to linear motion (the reciprocating translational movement of a coupler). 
     The conversion assembly  800  is best shown in  FIGS.  24 A- 26 H  and includes a drive wheel  810 , a bearing  815 , a linkage  820 , and a retainer  850 . 
     As best shown in  FIG.  24 B , the drive wheel  810  includes a generally cylindrical base  812  and a disc-shaped head  814  at one end of the base  812 . The base  812  and the head  814  are centered on and rotatable about a drive-wheel rotational axis A 810 . A linkage driveshaft  816  extends from the head  814  and is centered on a linkage rotational axis A 820 . The linkage driveshaft  816  is positioned near the perimeter of the head  814  so the linkage rotational axis A 820  is radially spaced apart from the drive-wheel rotational axis A 810 . 
     The linkage  820  includes a first link  830  and a second link  840 . The first link  830  includes a body  832  having a head and an opposing foot. A linkage-driveshaft mounting opening  834  is defined through the head of the body  832 . A first support engager  836  extends radially from the head of the body  832 . The foot of the body  832  includes one or more (here, two) stop fingers  838 . A second support engager  839  (here, a roller) is mounted between the stop fingers  838 . The second link  840  includes a body  842  having a head and an opposing foot. A coupler-mounting opening  844  is defined through the foot of the body  842 . Near the head, the body  842  includes a stop element  848  including one or more (here, two) stop surfaces  848   a . The first and second links  830  and  840  are connected to one another via a pivot  822  that extends between the foot of the body  832  of the first link  830  and the head of the body  842  of the second link  840 . The first and second links  830  and  840  are pivotable relative to one another about the pivot  822 . Once connected, the head of the body  832  of the first link  830  forms the head of the linkage  820  (and is referred to as such below), and the foot of the body  842  of the second link  840  forms the foot of the linkage  820  (and is referred to as such below). 
     As best shown in  FIG.  3 A , the base  812  of the drive wheel  810  is journaled in the drive-and-conversion-assembly-mounting element  340  of the support  300  via the bearing  815 , which is a roller bearing in this example embodiment, so the drive wheel  810  can rotate relative to the support  300  about the drive-wheel rotational axis A 810 . As best shown in  FIG.  24 A , the linkage driveshaft  816  of the drive wheel  810  is received in the linkage-driveshaft mounting opening  834  of the first link  830  of the linkage mount  820  to mount the linkage  820  to the drive wheel  810 . The retaining ring  850  is inserted into a groove (not labeled) defined around the perimeter of the linkage driveshaft  816  to retain the linkage  820  on the drive wheel  810 . Once mounted, the linkage  820  is rotatable relative to the drive wheel  810  about the linkage rotational axis A 820 . 
     Although not shown, the third transmission  750  is operably connected to the drive wheel  810  (such as via a shaft and suitable gearing) and configured to rotate the drive wheel  810  about the drive-wheel rotational axis A 810 . The foot of the linkage  820  is pivotably connected to the coupler  522  of the sealing assembly  500  via a pin (not labeled) that extends through the coupler-mounting opening  844 , as best shown in  FIGS.  3 A,  24 A, and  24 B , so the linkage  820  is pivotable relative to the coupler  522  about an axis A 844  ( FIG.  24 A ). Accordingly, the motor  710  is operatively coupled to the sealing assembly  500  (via the third transmission  750 , the second belt  760 , and the conversion assembly  800 ) and configured to control the sealing assembly  500  to carry out a sealing cycle, as described below. 
     More specifically, rotation of the motor output shaft  712  of the motor  710  in the second rotational direction causes rotation of the second belt pulley of the first transmission  720 . The second belt  760  transmits the output of the first transmission  720  (in this instance, the rotation of the second belt pulley) to the third transmission  750 , which in turn transmits the output of the first transmission  720  to the conversion assembly  800 . More specifically, the third transmission  750  transmits the output of the first transmission  720  to the drive wheel  810  of the conversion assembly  800 , which causes the drive wheel  810  to rotate about the drive-wheel rotational axis A 810 , carrying the linkage  820  with it. 
     The drive wheel  810  has a home position and a sealing position. In some embodiments, the sensor(s)  1700  include a home-position sensor configured to detect when the drive wheel  810  is at its home position and to communicate this to the controller  1300 . As best shown in  FIGS.  25 A and  26 A , when the drive wheel  810  is in its home position: the foot of the linkage  820  is at its home position (which is its uppermost position in this example embodiment); the sealing assembly  500  is in its home position; and the jaws  530 ,  534 ,  538 , and  542  are in their respective home positions. Upon initiation of the sealing cycle, the drive wheel  810  begins rotating (counterclockwise in this example embodiment) from its home position to its sealing position. As the drive wheel  810  rotates from its home position to its sealing position, the linkage  820  imparts a force on the coupler  522  that causes the coupler to force the sealing assembly  500  to move from its home position toward its sealing position. 
     After the sealing assembly  500  reaches its sealing position (and before the drive wheel  810  reaches its sealing position), continued rotation of the drive wheel  810  toward its sealing position causes the coupler  522  to move toward the jaws relative to the front and back plates  502  and  506  of the sealing assembly  500  (guided by the coupler pivot  524  received in the slot defined in the back plate). This causes downward movement of the upper ends of first and second coupler/jaw linkages  526  and  528 , which causes outward movement of the lower ends of the first and second coupler/jaw linkages  526  and  528 . This causes outward movement of the upper portions of the jaws. This causes inward movement of the lower portions of the jaws. In other words, this causes the jaws to pivot from their respective home positions to their respective sealing positions. The jaws are in their respective sealing positions when the foot of the linkage  820  reaches its sealing position (which is its lowermost position in this example embodiment) and the drive wheel  810  reaches its sealing position, as shown in  FIGS.  25 B and  26 F . Continued rotation of the drive wheel  810  back to its home position reverses the above movements: the jaws move from their sealing positions back to their home positions, and afterwards the sealing assembly moves back to its home position. 
     The components of the conversion assembly  800  are sized, shaped, positioned, oriented, and otherwise configured to change the distance between the head and the foot of the linkage during the sealing cycle. Put differently, the components of the conversion assembly  800  are sized, shaped, positioned, oriented, and otherwise configured to change the effective length of the linkage  820 —which in this example embodiment is the distance D between the axes A 820  and A 844 —during the sealing cycle to rapidly move the sealing assembly  500  toward its sealing position (by increasing the effective length of the linkage  820 ) and, after notching, back toward its home position (by decreasing the effective length of the linkage  820 ). The minimum effective length of the linkage  820  is DMIN, and the maximum effective length of the linkage  820  is DMAX, as shown in  FIGS.  25 A and  25 B . 
       FIGS.  26 A- 26 H  illustrate how the components of the conversion assembly  800  cooperate to change the effective length of the linkage  820  during the sealing cycle. At the start of the sealing cycle, the drive wheel  810  and the foot of the linkage  820  are at their respective home positions and the effective length of the linkage  820  is DMIN, as shown in  FIG.  26 A . The drive wheel  810  begins rotating from its home position to its sealing position, carrying the linkage  820  with it. As shown in  FIG.  26 B , this brings the second support engager  839  into contact with the second linkage engager  394 . Continued rotation of the drive wheel  810  causes the first link  830  to rotate counter-clockwise (from the viewpoint shown in  FIGS.  26 A- 26 H ) relative to the drive wheel  810  and the second link  840 , which causes the effective length of the linkage  820  to increase to its maximum DMAX as shown in  FIGS.  26 C- 26 E . As shown in  FIG.  26 E , just as the effective length of the linkage  820  reaches its maximum DMAX, the stop fingers  838  of the first link engage the stop surfaces  848   a  of the stop element  848  of the second link  848 , which prevents further rotation of the first link  830  relative to the second link  840 , and the second support engager  839  disengages the second linkage engager  394 . In this example embodiment, the sealing assembly  500  reaches its sealing position and the jaws begin moving from their home positions to their sealing positions before the effective length of the linkage  820  reaches its maximum DMAX. 
     After the effective length of the linkage  820  reaches DMAX, as the drive wheel  810  continues to rotate toward its sealing position, the linkage  820  maintains its effective length as the jaws continue moving from their home positions to their sealing positions. In this example embodiment, the jaws begin to contact the seal element (as described in detail below) just as the effective length of the linkage  820  reaches its maximum DMAX.  FIG.  26 F  shows the drive wheel  810  at its sealing position, at which point the jaws have also reached their sealing positions and notched the seal element and the strap. Afterwards, continued rotation of the drive wheel  810  brings the first support engager  836  into contact with the first linkage engager  392  of the base  300 , as shown in  FIG.  26 G . As the drive wheel  810  continues to rotate back to its home position, the engagement between the first support engager  836  and the first linkage engager  392  causes the first link  830  to rotate clockwise relative to the drive wheel  810  and the second link  140 . As shown in  FIG.  26 H , this relative rotation of the first link  830  causes the effective length of the linkage  820  to decrease from DMAX to DMIN by the time the drive wheel  810  reaches its home position. In this example embodiment, the sealing assembly  500  reaches its home position just as the effective length of the linkage  820  reaches its minimum DMIN. 
     The timing of movement of the sealing assembly  500  and the jaws relative to the rotation of the drive wheel  810  and the changing effective length of the linkage  820  may differ in other embodiments. For instance, in another embodiment, the sealing assembly  500  reaches its sealing position just as the effective length of the linkage  820  reaches its maximum DMAX, after which point the jaws begin moving to their sealing positions. 
     Varying the effective length of the linkage during the sealing cycle provides several benefits compared to prior art tools with linkages having a fixed effective length. Since the sealing assembly reaches its sealing position shortly after the start of the sealing cycle, more of the travel of the linkage-driveshaft as the drive wheel rotates from its home position to its sealing position is used to cut the notches in the seal element and the strap (as compared to prior art tools). This means that less force is required to cut the notches. In turn, the components of the jaw assembly—such as the jaws, gears, links, and the like—are lighter (and in some instances smaller) than those of prior art tools, rendering this tool lighter (and in some instances more compact) and therefore easier to handle. Since less force is required to cut the notches, the amount of torque the motor must provide is less than in prior art tools, meaning that the motor draws less current than in prior art tools and is more efficient. And this also allows the motor to run faster and therefore increase the speed of the sealing cycle as compared to prior art tools. 
     The display assembly  1300  includes a suitable display screen  1310  with a touch panel  1320 . The display screen  1310  is configured to display information regarding the strapping tool (at least in this embodiment), and the touch screen  1320  is configured to receive operator inputs such as a desired strap tension, desired weld cooling time, and the like as is known in the art. A display controller (not shown) may control the display screen  1310  and the touch panel  1320  and, in these embodiments, is communicatively connected to the controller  1300  to send signals to the controller  1300  and to receive signals from the controller  1300 . Other embodiments of the strapping tool do not include a touch panel. Still other embodiments of the strapping tool do not include a display assembly. 
     The actuating assembly  1400  is configured to receive operator input to start operation of the tensioning and sealing cycles. In this example embodiment, the actuating assembly  1400  includes first and second pushbutton actuators  1410  and  1420  that, depending on the operating mode of the strapping tool  50 , initiate the tensioning and/or sealing cycles as described below. Other embodiments of the strapping tool  50  do not have an actuating assembly  1400  and instead incorporate its functionality into the display assembly  1300 . For instance, in one of these embodiments two areas of the touch panel define virtual buttons that have the same functionality as mechanical pushbutton actuators. 
     The controller  1600  includes a processing device (or devices) communicatively connected to a memory device (or devices). For instance, the controller may be a programmable logic controller. The processing device may include any suitable processing device such as, but not limited to, a general-purpose processor, a special-purpose processor, a digital-signal processor, one or more microprocessors, one or more microprocessors in association with a digital-signal processor core, one or more application-specific integrated circuits, one or more field-programmable gate array circuits, one or more integrated circuits, and/or a state machine. The memory device may include any suitable memory device such as, but not limited to, read-only memory, random-access memory, one or more digital registers, cache memory, one or more semiconductor memory devices, magnetic media such as integrated hard disks and/or removable memory, magneto-optical media, and/or optical media. The memory device stores instructions executable by the processing device to control operation of the strapping tool  50 . The controller  1600  is communicatively and operably connected to the motor  710 , the display assembly  1300 , the actuating assembly  1400 , and the sensor(s)  1700  and configured to receive signals from and to control those components. The controller  1600  may also be communicatively connectable (such as via WiFi, Bluetooth, near-field communication, or other suitable wireless communications protocol) to an external device, such as a computing device, to send information to and receive information from that external device. 
     The controller  1600  is configured to operate the strapping tool in one of three operating modes: (1) a manual operating mode; (2) a semi-automatic operating mode; and (3) an automatic operating mode. In the manual operating mode, the controller  1600  operates the motor  710  to cause the tension wheel  440  to rotate responsive to the first pushbutton actuator  1410  being actuated and maintained in its actuated state. The controller  1600  operates the motor  710  to cause the sealing assembly  500  to carry out the sealing cycle responsive to the second pushbutton actuator  1420  being actuated. In the semi-automatic operating mode, the controller  1600  operates the motor  710  to cause the tension wheel  440  to rotate responsive to the first pushbutton actuator  1410  being actuated and maintained in its actuated state. Once the controller  1600  determines that the tension in the strap reaches the (preset) desired strap tension, the controller  1600  automatically operates the motor to cause the sealing assembly  500  to carry out the sealing cycle (without requiring additional input from the operator). In the automatic operating mode, the controller  1600  operates the motor  710  to cause the tension wheel  440  to rotate responsive to the first pushbutton actuator  1410  being actuated. Once the controller  1600  determines that the tension in the strap reaches the (preset) desired strap tension, the controller  1600  automatically operates the motor to cause the sealing assembly  500  to carry out the sealing cycle (without requiring additional input from the operator). 
     The power supply  1500  is electrically connected to (via suitable wiring and other components) and configured to power several components of the strapping tool  50 , including the motor  710 , the display assembly  1300 , the actuating assembly  1400 , the controller  1600 , and the sensor(s)  1700 . The power supply  1500  is a rechargeable battery (such as a lithium-ion or nickel cadmium battery) in this example embodiment, though it may be any other suitable electric power supply in other embodiments. The power supply  1500  is sized, shaped, and otherwise configured to be received in a receptacle (not labeled) defined by the housing  100 . The strapping tool  50  includes one or more battery-securing devices (not shown) to releasably lock the power supply  1500  in place upon receipt in the receptacle. Actuation of a release device of the strapping tool  50  or the power supply  1500  unlocks the power supply  1500  from the housing  100  and enables an operator to remove the power supply  1500  from the housing  100 . 
     Use of the strapping tool  50  to carry out a strapping cycle including: (1) a tensioning cycle in which the strapping tool  50  tensions a strap S around a load L; and (2) a sealing cycle in which the strapping tool  50  notches both a seal element SE positioned around overlapping top and bottom portions of the strap S and the top and bottom portions of the straps themselves and cuts the strap from the strap supply is described in accordance with  FIGS.  28 A- 28 C . Initially: the tensioning assembly  400  is in its strap-insertion position (held there by the retainer  1810 ); the sealing assembly  500  is in its home position; the jaws are in their respective home positions; the object blocker  605  is in its retracted position; the drive wheel  810  is in its home position; the rocker lever  910  is in its actuated position; and the gate  1010  is in its strap-insertion position. The strapping tool  50  is in the automatic mode for the purposes of this example. 
     The operator pulls the strap S leading-end first from a strap supply (not shown) and threads the leading end of the strap S through the seal element SE. While holding the seal element SE, the operator wraps the strap around the load L and positions the leading end of the strap S below another portion of the strap S, and again threads the leading end of the strap S through the seal element SE. Afterwards, the seal element SE is positioned around overlapping top and bottom portions of the strap S. The operator then bends the leading end of the strap S backward and slides the seal element SE along the strap S until it meets the bend.  FIG.  27    shows the position of the bend and the seal element SE at this point. 
     The operator then introduces the top portion of the strap S rearward of the seal element SE into the strap-receiving opening so the top portion of the strap S is between the tension wheel  440  and the roller  380  of the foot  320  of the support  300 . The operator then manually pulls the strap S to eliminate the slack and pushes the strapping tool  50  toward the seal element SE until the seal element SE engages the gate  1010  and is trapped between the bend in the bottom portion of the strap S and the gate  1010 . As shown in  FIG.  28 A , at this point the seal element SE is below the object blocker  605 . 
     The operator then actuates the first pushbutton actuator  1410  to initiate the strapping cycle. In response the controller  1600  starts the tensioning cycle by controlling the motor  710  to begin rotating the motor output shaft  712  in the first rotational direction, which causes the tension-wheel shaft  428   b  and tension wheel  440  thereon to begin rotating. Rotation of the tension-wheel shaft  428   b  forces the retainer  1810  to rotate to its release position. As this occurs, the tensioning-assembly-biasing element forces the tensioning assembly  400  to its strap-tensioning position. This causes the tension wheel  440  to engage the top portion of the strap S and pinch it against the roller  380 . At this point the bottom portion of the strap S is beneath the foot  320 . Movement of the tensioning assembly  400  back to the strap-tensioning position causes the gate  1010  to return to its home position in which the gate  1010  barely contacts or is just above the top portion of the strap. 
     As the tension wheel  440  rotates, it pulls on the top portion of the strap S, thereby tensioning the strap S around the load L. Throughout the tensioning cycle, the controller  1600  monitors the current drawn by the motor  710 . When this current reaches a preset value that is correlated with the (preset) desired strap tension for this strapping cycle, the controller  1600  stops the motor  710 , thereby terminating the tensioning cycle. 
     The controller  1600  then automatically starts the sealing cycle by controlling the motor  710  to begin rotating the motor output shaft  712  in the second rotational direction. As described in detail above, this causes the sealing assembly  500  to move to its sealing position. As the sealing assembly  500  moves to its sealing position, the object-blocker-lift element  630  frees the object blocker  605  to move toward its blocking position. The object blocker  605  contacts the seal element SE and is forced to remain in place by the seal element SE, as shown in  FIG.  28 B . The sealing assembly  500  is positioned relative to the seal element SE so the seal element SE is within the seal-element-receiving space of the sealing assembly  500  when in its sealing position. After the sealing assembly  500  reaches its sealing position, the jaws: (1) pivot from their respective home positions to their respective sealing positions to cut notches in the seal element SE and the top and bottom portions of the strap S within the seal element SE, as shown in  FIG.  28 C ; and then (2) pivot from their respective sealing positions back to their respective home positions to enable the strapping tool  50  to be removed from the strap S.  FIG.  29    shows the notched seal element SE and strap S. 
     Although the sealing assembly comprises jaws configured to cut into seal elements to attach two portions of the strap to itself, the sealing assembly may comprise other sealing mechanisms in other embodiments, such as a friction-welding assembly or a sealless-attachment assembly. 
     Other embodiments of the strapping tool may include fewer assemblies, components, and/or features than those included in the strapping tool  50  described above and shown in the Figures. For instance, other strapping tools may include fewer than all of (including only one of) and any combination of two or more of the conversion assembly, the object-blocking assembly, the retaining assembly, the retainer-activation assembly, the intermediary gearing, the double-pivoting rocker lever, the rocker lever with blocking finger, the decoupling assembly, jaw connectors with offset support surfaces, and the gate assembly. In other words, while the particular example strapping tool  50  described above includes all of these assemblies, components, and features, they are independent of one another and may be included in other strapping tools either alone or in any combination of two or more. 
     Various embodiments of the strapping tool comprise: a support comprising a foot; a tensioning assembly mounted to the support and pivotable relative to the foot of the support about a tensioning-assembly-pivot axis between a strap-tensioning position and a strap-insertion position, the tensioning assembly comprising a rotatable tension-wheel shaft, a tension wheel mounted to the tension-wheel shaft to rotate with the tension-wheel shaft, and tensioning-assembly gearing operably connected to the tension-wheel shaft to rotate the tension wheel about a tension-wheel rotational axis that is spaced-apart from the tensioning-assembly-pivot axis; intermediary gearing rotatable about the tensioning-assembly-pivot axis and operably connected to the tensioning-assembly gearing to drive the tensioning-assembly gearing; a rocker lever mounted to the tensioning assembly and pivotable relative to the tensioning assembly and about a rocker-lever pivot axis between a home position and an intermediate position, wherein the tensioning-assembly pivot axis is different from the rocker-lever pivot axis, wherein the rocker lever is pivotable relative to the support and about the tensioning-assembly pivot axis from the intermediate position to an actuated position to move the tensioning assembly from the strap-tensioning position to the strap-insertion position, wherein the rocker lever comprises blocking means for preventing the tensioning assembly from moving from the strap-tensioning position to the strap-insertion position when the rocker lever is in the home position; decoupling means for enabling the tension wheel to rotate about the tension-wheel rotational axis in a direction opposite a tensioning rotational direction, wherein the rocker lever is operably connected to the decoupling assembly to actuate the decoupling means when pivoted from the home position to the intermediate position; a sealing assembly mounted to the support and movable relative to the support between a sealing assembly home position and a sealing assembly sealing position, the sealing assembly comprising: spaced-apart first and second jaw connectors comprising first and second support surfaces, respectively; a central jaw connector positioned between the first and second jaw connectors and comprising a central support surface; a first pair of jaws between the first and central jaw connectors and comprising opposing first and second jaws pivotable between respective jaw home positions and jaw sealing positions; a second pair of jaws between the central and second jaw connectors and comprising opposing third and fourth jaws pivotable between respective jaw home positions and jaw sealing positions; wherein a strap path is defined between the first and second jaws and the third and fourth jaws and beneath the first, second, and central support surfaces, wherein the central support surface is closer to the strap path than the first and second support surfaces; a conversion assembly comprising a linkage operably connected to the sealing assembly and configured to move the sealing assembly from the sealing assembly home position to the sealing assembly sealing position and the jaws from their respective jaw home positions to their respective jaw sealing positions, the linkage comprising means for changing an effective length of the linkage while moving the sealing assembly from the sealing assembly home position to the sealing assembly sealing position; drive means for driving the intermediary gearing and the conversion assembly; retaining means for retaining the tensioning assembly in the strap-insertion position; deactivating means for preventing the retaining means from retaining the tensioning assembly in the strap-insertion position. 
     Various embodiments of the strapping tool comprise: a support comprising a foot; a housing comprising a handle and defining a blocking-finger opening, the housing at least partially enclosing the support; a tensioning assembly mounted to the support and pivotable relative to the foot of the support about a tensioning-assembly-pivot axis between a strap-tensioning position and a strap-insertion position, the tensioning assembly comprising a rotatable tension-wheel shaft, a tension wheel mounted to the tension-wheel shaft to rotate with the tension-wheel shaft, and tensioning-assembly gearing operably connected to the tension-wheel shaft to rotate the tension wheel about a tension-wheel rotational axis that is spaced-apart from the tensioning-assembly-pivot axis; intermediary gearing rotatable about the tensioning-assembly-pivot axis and operably connected to the tensioning-assembly gearing to drive the tensioning-assembly gearing; a rocker lever mounted to the tensioning assembly and pivotable relative to the tensioning assembly and about a rocker-lever pivot axis between a home position and an intermediate position, wherein the tensioning-assembly pivot axis is different from the rocker-lever pivot axis, wherein the rocker lever is pivotable relative to the support and about the tensioning-assembly pivot axis from the intermediate position to an actuated position to move the tensioning assembly from the strap-tensioning position to the strap-insertion position, wherein the rocker lever comprises a blocking finger positioned and oriented such that movement of the rocker lever from the home position to the intermediate position causes the blocking finger to pass through the blocking-finger opening and into the housing, and the blocking finger prevents the tensioning assembly from moving from the strap-tensioning position to the strap-insertion position when the rocker lever is in the home position; a decoupling assembly actuatable to enable the tension wheel to rotate about the tension-wheel rotational axis in a direction opposite a tensioning rotational direction, wherein the rocker lever is operably connected to the decoupling assembly to actuate the decoupling assembly when pivoted from the home position to the intermediate position; a sealing assembly mounted to the support and movable relative to the support between a sealing assembly home position and a sealing assembly sealing position, the sealing assembly comprising: spaced-apart first and second jaw connectors comprising first and second support surfaces, respectively; a central jaw connector positioned between the first and second jaw connectors and comprising a central support surface; a first pair of jaws between the first and central jaw connectors and comprising opposing first and second jaws pivotable between respective jaw home positions and jaw sealing positions; a second pair of jaws between the central and second jaw connectors and comprising opposing third and fourth jaws pivotable between respective jaw home positions and jaw sealing positions; wherein a strap path is defined between the first and second jaws and the third and fourth jaws and beneath the first, second, and central support surfaces, wherein the central support surface is closer to the strap path than the first and second support surfaces; a conversion assembly comprising a linkage comprising a first link and a second link connected to one another, wherein the linkage is operably connected to the sealing assembly and configured to move the sealing assembly from the sealing assembly home position to the sealing assembly sealing position and the jaws from their respective jaw home positions to their respective jaw sealing positions, wherein the first and second links are configured to move relative to one another to change an effective length of the linkage while moving the sealing assembly from the sealing assembly home position to the sealing assembly sealing position; a drive assembly comprising a motor operably connected to the intermediary gearing to rotate the intermediary gearing about the tensioning-assembly pivot axis in the tensioning rotational direction and operably connected to the conversion assembly and configured to drive the linkage; a retainer comprising a body having a tension-wheel-shaft engager, wherein the retainer is movable relative to the tension-wheel shaft between a release position and a retaining position; a retainer-biasing element biasing the retainer to the retaining position; and 
     a retainer engager movable relative to the retainer between an activated position and a deactivated position, wherein when the tensioning assembly is in the strap-insertion position and the retainer is in the retaining position, the tension-wheel-shaft engager of the retainer engages the tension-wheel shaft of the tensioning assembly to retain the tensioning assembly in the strap-insertion position, wherein when the retainer engager is in the deactivated position, the retainer engager prevents the retainer from moving to the retaining position, wherein when the retainer engager is in the activated position, the retainer engager enables the retainer to move to the retaining position.