STRAPPING TOOL WITH ENERGY-RELEASE FEATURE

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 via a cam-driven sealing assembly to form a tensioned strap loop around the load.

BACKGROUND

Strapping devices 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. Battery-powered strapping tools are one type of strapping device. 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).

In certain known sealless strapping tools, the dies are mounted to a die assembly that is lowered to force the overlapping portions of the strap against the punch and, eventually, form the interlocking cuts in the strap. After forming the cuts, the strap and other mechanical components of the strapping tool store significant potential energy that exerts a significant force on the die assembly, which can cause issues when the die assembly begins moving back upward to release the strap.

SUMMARY

Various embodiments of the present disclosure provide a strapping tool with a sealing assembly supported by a support and including a pivotable die assembly and a rotatable camshaft. The camshaft includes a cam having a variable diameter cam surface that engages a cam follower of the die assembly. The cam surface is shaped so rotation of the camshaft during a sealing cycle causes the cam to force the die assembly to pivot from a home position to a sealing position so one or more dies of the die assembly cooperate with a punch on the support to form interlocking cuts in two overlapping strap portions. Continued rotation of the cam results in the die assembly pivoting back to its home position during an energy-release phase and a return phase of the sealing cycle. During the energy-release phase, the shape of the cam enables the die assembly to pivot a relatively small amount as potential energy built up in the strap and other components of the strapping tool is released. During the return phase after this energy is released, the shape of the cam enables the die assembly to pivot a relatively large amount back to its home position.

BRIEF DESCRIPTION OF THE FIGURES

FIGS. 1A and 1B are perspective views of one example embodiment of a strapping tool of the present disclosure.

FIG. 1C is a block diagram of certain components of the strapping tool of FIGS. 1A and 1B.

FIGS. 2A-2C are diagrammatic views of the strapping tool of FIGS. 1A and 1B securing a load to a pallet.

FIG. 2D is a perspective view of a sealless joint formed by the strapping tool of FIG. 1A to attach two overlapping portions of strap.

FIGS. 3A and 3B are perspective views of the working assembly of the strapping tool of FIGS. 1A and 1B.

FIG. 3C is a partial side view of the working assembly of FIGS. 3A and 3B showing upper and lower strap portions extending between the die assembly of the sealing assembly and the support and between the tension wheel and the support.

FIG. 4A is a partial side view of the strapping tool of FIGS. 1A and 1B with part of the front housing section of the housing removed and with the tensioning assembly in the strap-tensioning position.

FIG. 4B is a partial side view similar to FIG. 4A but with the tensioning assembly in the strap-insertion position.

FIG. 5A is a perspective view of the tensioning-assembly gearing and the tension wheel of the tensioning assembly of the working assembly of FIGS. 3A and 3B.

FIG. 5B is a cross-sectional perspective view of the tensioning-assembly gearing and the tension wheel of FIG. 5A taken along line 5B-5B of FIG. 5A.

FIG. 5C is an exploded perspective view of the tensioning-assembly gearing and the tension wheel of FIG. 5A.

FIG. 6A is a perspective view of the decoupling assembly of the working assembly of FIGS. 3A and 3B.

FIG. 6B is an exploded perspective view of the decoupling assembly of FIG. 6A.

FIG. 6C is a cross-sectional perspective view of part of the working assembly of FIGS. 3A and 3B taken along line 6C-6C of FIG. 3B, which extends through the decoupling assembly of FIG. 6A.

FIGS. 7A and 7B are perspective views of the die assembly of the sealing assembly of the working assembly of FIGS. 3A and 3B.

FIG. 8 is a perspective view of the camshaft, the first and second cams, and the sealing-assembly gearing of the sealing assembly of the working assembly of FIGS. 3A and 3B.

FIG. 9 is an end-on view of the camshaft and the first and second cams of FIG. 8.

FIG. 10 is a perspective view of the motor assembly of the working assembly of FIGS. 3A and 3B.

FIG. 11 is a cross-sectional perspective view of the working assembly of FIGS. 3A and 3B taken along line 11-11 of FIG. 3B, which extends through the motor assembly of FIG. 10 and the transmission assembly of the working assembly.

FIG. 12A is a side view of the working assembly of FIGS. 3A and 3B with the first and second cams of FIG. 8 and the die assembly of FIGS. 7A and 7B in their respective home positions at the start of the sealing cycle.

FIG. 12B is a side view corresponding to FIG. 12A but after the strap-engage phase of the sealing cycle with the die of the die assembly positioned to just contact the upper strap portion.

FIG. 12C is a side view corresponding to FIGS. 12A and 12B but after the strap-cut phase of the sealing cycle with the die assembly in its sealing position.

FIG. 12D is a side view corresponding to FIGS. 12A-12C but after the energy-release phase of the sealing cycle with the die assembly pivoted slightly back toward its home position.

FIG. 12E is a side view corresponding to FIGS. 12A-12D but after the release phase of the sealing cycle with the first cam and second cams and the die assembly back at their respective home positions.

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. 1A-12E show one example embodiment of a strapping device of the present disclosure in the form of a strapping tool 50 (sometimes referred to as the “tool” in the Detailed Description for brevity) and certain assemblies and components thereof. As shown in FIGS. 2A-2C, the strapping tool 50 is configured to carry out a strapping cycle to tension and seal strap S (metal strap in this example embodiment) around a load L on a pallet P to form a tensioned strap loop that secures the load L to the pallet P. An operator pulls strap S from a strap supply (not shown) and wraps the strap around the load L and through the openings in the pallet P until a lower portion LP of the strap S (which includes the leading end of the strap S) is positioned below an upper portion UP of the strap S, as shown in FIG. 2A. The operator then introduces the overlapped upper and lower portions UP and LP of the strap S into the strapping tool 50 and actuates one or more buttons to initiate the strapping cycle. As shown in FIG. 2B, a motor drives a tensioning assembly to carry out a tensioning cycle during which the strapping tool 50 tensions strap S around the load L. Once a preset tension is reached in the strap S, as shown in FIG. 2C, the motor drives a sealing assembly to carry out a sealing cycle during which the strapping tool 50 cuts keys K into the upper and lower portions UP and LP of the strap S, as shown in FIG. 2D, and cuts the strap S from the strap supply. Since the strap S is under tension, cutting the strap from the strap supply causes the upper portion UP to slide relative to the lower portion LP to mechanically interlock the keys K to form a sealless strap joint J, as shown in FIG. 2D.

The strapping tool 50 includes a housing 100 (FIGS. 1A and 1B), a working assembly 200 (FIGS. 3A-3C), a display assembly 1300 (FIGS. 1A-2), an actuating assembly 1400 (FIGS. 1A-1C); a power supply (not shown); a controller 1600 (FIG. 1C), and one or more sensors 1700 (FIG. 1C).

The housing 100, which is best shown in FIGS. 1A and 1B, 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. In this example embodiment, the housing 100 includes a front housing section 110, a rear housing section 120, a motor housing section 130, and a handle section 150. The front housing section 110 at least partially encloses and/or supports at least some of the components of the working assembly 200 and the actuating assembly 1400. The rear housing section 120 at least partially encloses and/or supports at least some of the components of the display assembly 1300 and defines a receptacle 122 sized, shaped, and otherwise configured to receive and at least partially enclose and/or support the power supply and the controller 1600. The motor housing section 130 extends between and connects the bottoms of the front and rear housing sections 110 and 120 and at least partially encloses and/or supports at least some of the components of the working assembly 200 (and in particular, the motor assembly 900, as further described below). The handle housing section 150 extends between and connects the tops of the front and rear housing sections 110 and 120 and defines a handle used by the operator. 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, which is best shown in FIGS. 3A, 3B, and 8-9C, 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 500, a sealing assembly 600, a rocker lever 700, a transmission assembly 800, a motor assembly 900, and a decoupling assembly 1900.

The support 300, which is best shown in FIGS. 3A4B, serves as a direct or indirect common mount for the tensioning assembly 500, the sealing assembly 600, the rocker lever 700, the transmission assembly 800, the motor assembly 900, and the decoupling assembly 1900. The support 300 includes a base 310, first and second support ears 320 and 330 extending upward from the base 310, a die-assembly mounting ear (not shown) extending forward from the base 310, and a mounting shaft 390 extending through and rotatably supported by the support ears 320 and 330. The base 310 supports a tensioning plate 312 below the tensioning wheel 590 of the tensioning assembly 500 (described below) and a punch 314 below the dies 614 of the die assembly 610 (described below).

The tensioning assembly 500, which is best shown in FIGS. 5A-5C, is configured to tension the strap around the load during the tensioning cycle. The tensioning assembly 500 includes a tensioning-assembly support 505, tensioning-assembly gearing 510, and a tension wheel 590 driven by the tensioning-assembly gearing 510.

The tensioning-assembly gearing 510 includes: a gearing support 512; a driven shaft 522; a tensioning-assembly-gearing freewheel 523; first planet gears 524a, 524b, 524c, and 524d; a carrier 525; a first ring gear 526; a bushing 527; a second ring gear 528; a tension-wheel mount 529; and second planet gears 530a, 530b, and 530c. Certain components of the tensioning-assembly gearing 510 are centered on and certain components of the tensioning-assembly gearing 510 are rotatable about a tension-wheel rotational axis A590. The gearing support 512 includes an annular support shaft 512a and a cover 512b extending radially outward from the support shaft 512a. The driven shaft 522 includes a shaft portion 522a and a first sun gear 522b at one end of the shaft portion 522a. The carrier 525 includes a first planet-gear carrier 525a to which the first planet gears 524a-524d are rotatably mounted (such as via respective bearings and mounting pins) and a second sun gear 525b rotatable with (and here integrally formed with) the planet-gear carrier 525a about the tension-wheel rotational axis A590. The first ring gear 526 includes internal teeth 526it and external teeth 526ot. The second ring gear 528 includes internal teeth 528it. The tension-wheel mount 529 includes a second planet-gear carrier 529a and a tension-wheel shaft 529b rotatable with (and here integrally formed with) the second planet-gear carrier 529a about the tension-wheel rotational axis A590. The second planet gears 530a-530c are rotatably mounted to the second planet-gear carrier 529a (such as via respective bearings and mounting pins). The tension-wheel shaft 529b includes a splined end 529s opposite the second planet-gear carrier 529a to enable the tension wheel 590 to be mounted thereon and fixed in rotation with the tension-wheel shaft 529.

The shaft portion 522a of the driven shaft 522 extends through and is engaged by the tensioning-assembly-gearing freewheel 523, which is itself supported by and positioned within a bore through the annular support shaft 512a of the gearing support 512. The tensioning-assembly-gearing freewheel 523 is configured to permit rotation of the driven shaft 522 relative to the gearing support 512 in a tensioning rotational direction—referred to as the tensioning direction T (FIG. 5A)—and to prevent rotation of the driven shaft 522 in a rotational direction opposite the tensioning direction T—referred to as the release direction T_REV(FIG. 5A). The first sun gear 522b of the driven shaft 522 meshes with and drivingly engages the first planet gears 524a-524d. The first planet gears 524a-524d mesh with the internal teeth 526it of the first ring gear 526. The bushing 527 rotatably supports the first ring gear 526 and separates it from the second ring gear 528. The second sun gear 525b meshes with and drivingly engages the second planet gears 530a-530c. The second planet gears 530a-530c mesh with the internal teeth 528it of the second ring gear 528. The tension wheel 590 is mounted to the splined end 529s of the tension-wheel shaft 529b and held in place longitudinally via a suitable retainer such that the tension-wheel shaft 529b and the tension wheel 590 rotate together about the tension-wheel rotational axis A590. Any other suitable method, such as a key, may be used to fix the tension wheel in rotation with the tension-wheel shaft.

The tensioning-assembly gearing 510 is mounted to the tensioning-assembly support 505 via attaching the cover 512b of the gearing support 512 to the tensioning-assembly support 505. The second ring gear 528 is fixed in rotation about the tension-wheel rotational axis A590 relative to the tensioning-assembly support 505 (that is, the second ring gear 528 is not rotatable about the tension-wheel rotational axis A590 relative to the tensioning-assembly support 505). In this example embodiment, pins (not shown) are positioned between the outer surface of the second ring gear 528 and the tensioning-assembly support 505 to prevent relative rotation, though any suitable components (such as set screws, adhesive, 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 526 in rotation about the tension-wheel rotational axis A590 relative to the tensioning-assembly support 505 so the first ring gear 526 cannot rotate about the tension-wheel rotational axis A590 relative to the tensioning-assembly support 505.

During the tensioning cycle, the motor assembly 900 and transmission assembly 800 drive the driven shaft 522 in the tensioning direction T, as described below. This causes the first sun gear 522b to rotate about the tension-wheel rotational axis A590 in the tensioning direction T. The first sun gear 522a drives the first set of planet gears 524a-524dc. Since the decoupling assembly 1900 prevents the first ring gear 526 from rotating about the tension-wheel rotational axis A590, rotation of the planet gears 524a-524d causes the carrier 525—including the second sun gear 525b—to rotate about the tension-wheel rotational axis A590 in the tensioning direction T. The second sun gear 525b drives the second set of planet gears 530a-530c. Since the second ring gear 528 cannot rotate about the tension-wheel rotational axis A590, rotation of the planet gears 530a-530c causes the tension-wheel mount 529 and the tension wheel 590 mounted thereto to rotate about the tension-wheel rotational axis A590 in the tensioning direction T. Accordingly, the tensioning-assembly gearing 510 operatively connects the motor assembly 900 and the transmission assembly 800 to the tension wheel 590 to rotate the tension wheel 590 about the tension-wheel rotational axis A590 in the tensioning direction T.

The tensioning assembly 500 is movably mounted to the mounting shaft 390 of the support 300 and configured to pivot relative to the support 300—and particularly relative to the base 310 of the support 300—under control of the rocker lever 700 (as described below) and about a tensioning-assembly-pivot axis A500 between a strap-tensioning position (FIG. 4A) and a strap-insertion position (FIG. 4B). When the tensioning assembly 500 is in the strap-tensioning position, the tension wheel 590 is adjacent to the tensioning plate 312 of the support 300 (or the upper surface of the upper portion of the strap if the strap has been inserted into the strapping tool 50). When the tensioning assembly 500 is in the strap-insertion position, the tension wheel 590 is spaced-apart from the tensioning plate 312 to enable the overlapping upper and lower portions of the strap to be inserted between the tension wheel 590 and the tensioning plate 312. One or more springs or other biasing elements (not shown) bias the tensioning assembly 500 to the strap-tensioning position.

The decoupling assembly 1900, which is best shown in FIGS. 6A-6C, is configured to (when actuated) enable the tension wheel 590 to rotate about the tension-wheel rotational axis A590 in the release direction T_REV—(i.e., the rotational direction opposite the tensioning direction T—to release the tension in the strap after completion of the tensioning cycle but before completion of the sealing cycle. The decoupling assembly 1900 includes a decoupling-assembly shaft 1910, a first engageable element 1920, a second engageable element 1930, an expandable element 1940, a retainer 1950, a washer 1960, and a threaded fastener 1970.

The decoupling-assembly shaft 1910 includes a body 1912 having a first end 1912a having an irregular cross-section and second end 1912b having radially extending teeth around its circumference. A first support 1914 extends from the first end 1912a, and a second support 1916 extends from the second end 1912b. 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 1912a of the body 1912 of the decoupling-assembly shaft 1910. The second engageable element 1930 includes a tubular body 1932 and an annular flange 1934 at one end of the body 1932. An opening 19340 is defined through the flange 1934. The expandable element 1940 includes a torsion spring having a first end 1940a and a second end 1940b.

As best shown in FIGS. 6A and 6C, the first engageable element 1920 is mounted on the first end 1912a of the body 1912 of the decoupling-assembly shaft 1910 for rotation therewith about a decoupling-assembly rotational axis A1900. The second engageable element 1930 circumscribes the first support 1914 of the body 1912 of the decoupling-assembly shaft 1910 and is positioned such that the body 1932 is adjacent and coaxial with the first engageable element 1920. The expandable element 1940, which is a torsion spring in this example embodiment, circumscribes the first engageable element 1920 and the body 1932 of the second engageable element 1930. The outer diameters of the first engageable element 1920 and the body 1932 of the second engageable element 1930 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 compressive force on the first engageable element 1920 and the body 1932 of the second engageable element 1930 that prevents those components (and the decoupling-assembly shaft 1910) from rotating relative to one another about the decoupling-assembly rotational axis A1900. The second end 1940b of the expandable element 1940 is received in the opening 19340 defined through the flange 1934 of the second engageable element 1930.

As best shown in FIG. 6C, the decoupling assembly 1900 is mounted to the tensioning-assembly support 505 and operatively connected to the tensioning-assembly gearing 510. More specifically, the decoupling assembly 1900 is mounted to the tensioning-assembly support 505 via the fastener 1970, which fixes the second engageable element 1930 in rotation relative to the tensioning-assembly support 505 such that the second engageable element 1930—and the second end 1940b of the expandable element 1940 received in the opening 19340 of the flange 1934 of the second engageable element 1930—cannot rotate relative to the tensioning-assembly support 505 about the decoupling-assembly rotational axis A1900. The retainer 1950 and washer 1960 separate the first engageable element 1920 from the tensioning-assembly support 505. An intermediary gear 1990 mounted to (and freely rotatable relative to) the tensioning-assembly support 505 operably connects the body 1912 of the decoupling-assembly shaft 1910 to the first ring gear 526 of the tensioning-assembly gearing 510. Specifically, the teeth on the second end 1912b of the body 1912 of the decoupling-assembly shaft 1910 mesh with teeth of the intermediary gear 1990, which also mesh with the outer teeth 526ot of the first ring gear 526 of the tensioning-assembly gearing 510 of the tensioning assembly 500. Since the body 1932 is fixed in rotation relative to the tensioning-assembly support 505 and the decoupling-assembly shaft 1910 is fixed in rotation with the first engageable element 1920, the decoupling-assembly shaft 1910—and thus the intermediary gear 1990—is fixed in rotation relative to the tensioning-assembly support 505. Since the intermediary gear 1990 meshes with the outer teeth 526ot of the first ring gear 526 of the tensioning-assembly gearing 510, the decoupling assembly 1900 prevents the first ring gear 526 from rotating about the tension-wheel rotational axis A590.

The decoupling assembly 1900 is actuatable (such as by the rocker 700 as described below) to eliminate the connection between the torsion spring 1940 and the first engageable element 1920 such that the first engageable element 1920 and the decoupling-assembly shaft 1910 may rotate relative to the second engageable element 1930 about the decoupling-assembly rotational axis A1900. As explained above, the second engageable element 1930 and the second end 1940b of the expandable element 1940 (that is received in the opening 19340 of the flange 1934 of the second engageable element 1930) are fixed in rotation relative to the tensioning-assembly support 505. To eliminate the connection between the torsion spring 1940 and the first engageable element 1920, the first end 1940a of the torsion spring 1940 is rotated decoupling-assembly rotational axis A1900 relative to the tensioning-assembly support 505, the second end 1940b of the torsion spring 1940, and the second engageable element 1930 (such as via moving the rocker lever 700 from the home position to the intermediate position). As this occurs, the inner diameter of the torsion spring 1940 near its first end 1940a begins expanding, and eventually expands enough (thereby reducing the compression force or eliminating it altogether) to enable the first engageable element 1920 and the decoupling-assembly shaft 1910 to rotate decoupling-assembly rotational axis A1900 relative to the second engageable element 1930 (and the torsion spring 1940).

Upon completion of the tensioning cycle, the tension wheel 590 holds a significant amount of tension in the strap, and the strap exerts a counteracting force (or torque) on the tension wheel 590 in the release direction T_REV. Actuation of the decoupling assembly 1900 enables the tension wheel 590 to rotate in the release direction T_REVto release that tension in a controlled manner. Specifically, upon completion of the tensioning cycle, the decoupling-assembly shaft 1910 (via the intermediary gear 1990) continues to prevent the first ring gear 526 of the tensioning-assembly gearing 510 from rotating about the tension-wheel rotational axis A590, which prevents the tension wheel 590 from rotating in the release direction T_REV. As the first end 1940a of the torsion spring 1940 is rotated about the decoupling-assembly rotational axis A1900, the inner diameter of the torsion spring 1940 near its first end 1940a begins expanding. Eventually, the force the first ring gear 526 exerts on the decoupling-assembly shaft 1910 exceeds the compression force the torsion spring 1940 exerts on the first engageable element 1920. When this occurs, the first ring gear 526 rotates in the release direction T_REVabout the tension-wheel rotational axis A590. Since the tensioning-assembly-gearing freewheel 523 prevents the driven shaft 522—including the first sun gear 522b—from rotating in the release direction T_REV, this causes the first planetary gears 524a-524d to rotate in the release direction T_REVabout the tension-wheel rotational axis A590. This (as explained above) causes the tension wheel 590 to rotate in the release direction T_REVabout the tension-wheel rotational axis A590.

In other embodiments, the second end of the body of the decoupling-assembly shaft directly meshes with the outer teeth of the first ring gear (rather than via one or more intermediary gears).

The rocker lever 700, which is best shown in FIGS. 3A-4B, is operably connected to: (1) the tensioning assembly 500 and configured to move the tensioning assembly 500 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 590 to rotate in the release direction T_REV. The rocker lever 700 includes a mounting head 710, a body 720 connected to the mounting head 710, and a decoupling-assembly actuator 730 (a pin in this example embodiment) extending transversely from the body 720.

The mounting head 710 is pivotably mounted to the mounting shaft 390 of the support 300 such that the rocker lever 700 is pivotable relative to the support 300 about a rocker-lever pivot axis A700 (which in this example embodiment is the same as the tensioning-assembly-pivot axis A500). The rocker lever 700 is also mounted to the tensioning-assembly 500 via pin 700p that extends through the tensioning-assembly support 505 and a slot (not shown) defined through the body 720 of the rocker lever 700. The slot is sized, shaped, and oriented such that the rocker lever 700 is pivotable about the tensioning-assembly-pivot axis A500: (1) relative to the support 300, the tensioning assembly 500, and the decoupling assembly 1900 from a home position (FIGS. 3A-4A) to an intermediate position (not shown) to actuate the decoupling assembly 1900; and (2) relative to the support 300 from the intermediate position (not shown) to an actuated position (FIG. 4B). A rocker-lever biasing element (not shown), such as a spring, biases the rocker lever to the home position.

More specifically, when the rocker lever 700 is in the home position, as shown in FIGS. 3A-4A, the tensioning assembly 500 is in its strap-tensioning position. As the rocker lever 700 moves relative to the support 300, the tensioning assembly 500, and the decoupling assembly 1900 to the intermediate position, the decoupling-assembly actuator 730 engages the first end 1940a of the torsion spring 1940 of the decoupling assembly 1940 and rotates that first end relative to the tensioning-assembly support 505, the second end 1940b of the torsion spring 1940, and the first and second engageable elements 1920 and 1930. As this occurs, the inner diameter of the torsion spring 1940 near its first end 1940a begins expanding, and eventually expands enough (thereby reducing the compression force or eliminating it altogether) to enable the first engageable element 1920 and the decoupling-assembly shaft 1910 to rotate relative to the second engageable element 1930 and the torsion spring 1940. After the rocker lever 700 reaches the intermediate position, continued movement of the rocker lever 700 toward the actuated position causes the tensioning assembly 500 to begin pivoting with the rocker lever 700, culminating in the rocker lever 700 reaching the actuated position and the tensioning assembly 500 reaching the strap-insertion position.

The sealing assembly 600, which is best shown in FIGS. 3A, 3B, and 7A-9, 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 forming a set of mechanically interlocking cuts (or keys) in the overlapping portions of the strap. The sealing assembly 600 includes a die assembly 610, a camshaft 620 including a first cam 622 and a second cam 624, and sealing-assembly gearing 630.

The die assembly 610, best shown in FIGS. 7A and 7B, is movable to engage the strap and cooperate with the punch 314 of the support 300 to form interlocking cuts (or keys) in the overlapping portions of the strap. The die assembly 610 includes a body 611 including two spaced-apart mounting ears 611e1 and 611e2; a first cam follower 612 mounted to the upper surface of the body 611; a mounting arm 613 supporting a second cam follower 613f, extending from the body 611, and curving over the first cam follower 612; two spaced-apart dies 614 on the underside of the body 611; and a cutter 616 supported by the body 611 rearward of the dies 614. The die assembly 610 is mounted to the support 300 via: (1) a mounting pin 605 extending through the mounting ears 611e1 and 611e1 and the die-assembly mounting ear of the support 300; and (2) a mounting pin (not labeled) connecting the mounting arm 613 to the first mounting ear 320 of the support 300. This mounting configuration enables the die assembly 610 to pivot relative to the support 300—and particularly relative to the base 310 of the support 300—under control of the first and second cams 622 and 624 of the camshaft 620 and about a die-assembly-pivot axis A610 between a home position (FIGS. 3A and 12A) and a sealing position (FIG. 12C), as explained in detail below. A die-assembly biasing element (not shown) biases the die assembly 610 to its home position.

The camshaft 620, which is best shown in FIGS. 8 and 9, controls the position of the die assembly 610 during the sealing cycle. In this example embodiment, the total angular displacement of the camshaft 620 is 360 degrees (i.e., one complete rotation) for a single sealing cycle. The camshaft 620 is elongated and includes first and second cams 622 and 624 near one end and a splined end 620s opposite the first and second cams 622 and 624 that enables the camshaft 620 to be mounted to and fixed in rotation with the planet-gear carrier 634 of the sealing-assembly gearing 630 (described below).

The first cam 622 has a cam surface 622s with a varying radius (as measured from the camshaft rotational axis A620). The cam surface 622s is divided into four angular sections 622s1, 622s2, 622s3, and 622s4 that, as explained below, correspond to four phases of the sealing cycle and different positions of the die assembly 610. The four phases of the sealing cycle include: (1) a strap-engage (first) phase during which the camshaft (and the first cam) rotates a first cam angular displacement Φ₁(FIG. 9) and the die assembly 610 pivots a first die-assembly angular displacement from its home position toward its sealing position until the dies 614 contact the upper strap portion; (2) a strap-cut (second) phase during which the camshaft (and the first cam) rotates a second cam angular displacement Φ₂(FIG. 9) and the die assembly 610 pivots a second die-assembly angular displacement to its sealing position, at which point the dies 614 have cooperated with the punch 314 of the support 300 to cut the strap and the cutter 616 has cut the strap from the strap supply; (3) an energy-release (third) phase during which the camshaft (and the first cam) rotates a third cam angular displacement Φ₃(FIG. 9) and the die-assembly biasing element, the strap, and other mechanical components of the sealing assembly 600 force the die assembly 610 to gradually pivot a third die-assembly angular displacement back upward toward its home position to release significant potential energy; and (4) a return (fourth) phase during which the camshaft (and the first cam) rotates a fourth cam angular displacement Φ₄(FIG. 9) and the die-assembly biasing element quickly forces the die assembly 610 to pivot a fourth die-assembly angular displacement to complete the move back to its home position.

In this example embodiment, the first die-assembly angular displacement is approximately 4 degrees, the second die-assembly angular displacement is approximately 5 degrees, the third die-assembly angular displacement is approximately 1.4 degrees, and the fourth die-assembly angular displacement is approximately 7.6 degrees, though these values may vary in other embodiments. Accordingly, the first die-assembly angular displacement is less than the second die-assembly angular displacement, and the third die-assembly angular displacement is less than the fourth die-assembly angular displacement.

In this example embodiment, the first cam angular displacement is approximately 55 degrees, the second cam angular displacement is approximately 166 degrees, the third cam angular displacement is approximately 78 degrees, and the fourth cam angular displacement is approximately 61 degrees, though these values may vary in other embodiments. Accordingly, the second cam angular displacement is greater than the first and third cam angular displacements, and the third cam angular displacement is greater than the fourth cam angular displacement.

The first angular section 622s1 corresponds to the strap-engage phase and the first cam angular displacement and features an increase in radius moving in the sealing direction S from R1 to R2. In this example embodiment, R2 is approximately 1.5×R1, which combined with the relatively short first cam angular displacement makes this a relatively sharp increase. The second angular section 622s2 corresponds to the strap-cut phase and the second cam angular displacement and features an increase in radius moving in the sealing direction S from R2 to R3. In this example embodiment, R3 is approximately 1.4×R2, which combined with the relatively large second cam angular displacement makes this a relatively gradual increase. The third angular section 622s3 corresponds to the energy-release phase and the third cam angular displacement and features a decrease in radius moving in the sealing direction S from R3 to R4. In this example embodiment, R4 is approximately 0.9×R3, which combined with the relatively large third cam angular displacement makes this a relatively gradual decrease. The fourth angular section 622s4 corresponds to the return phase and the fourth cam angular displacement and features a decrease in radius moving in the sealing direction S from R4 to R1. In this example embodiment, R1 is approximately 0.5×R4, which combined with the relatively short fourth cam angular displacement makes this a relatively sharp decrease. The radii multiples are merely examples and may be any other suitable multiples in other embodiments.

Accordingly, during the sealing cycle (i.e., a 360 degree rotation of the camshaft 620): (1) the angular displacement of the first cam 622 during the strap-engage phase (when the first angular section 622s1 contacts the first cam follower 612) is a first cam angular displacement of approximately 60 degrees; (2) the angular displacement of the first cam 622 during the strap-cut phase (when the second angular section 622s2 contacts the first cam follower 612) is a second cam angular displacement of approximately 150 degrees: (3) the angular displacement of the first cam 622 during the energy-release phase (when the third angular section 622s3 contacts the first cam follower 612) is a third cam angular displacement of approximately 90 degrees; and (4) the angular displacement of the first cam 622 during the return phase (when the fourth angular section 622s4 contacts the first cam follower 612) is a fourth cam angular displacement of approximately 60 degrees. In other words, in this example embodiment, the second cam angular displacement is greater than the first cam angular displacement, and the third cam angular displacement is greater than the fourth cam angular displacement. And in this example embodiment, the second cam angular displacement is greater than the third cam angular displacement (though they need not be in other embodiments), and the first and fourth cam angular displacements are the same (though they need not be in other embodiments).

In this example embodiment, the motor assembly 900 drives the camshaft 620 at a generally constant torque velocity during the sealing cycle. A strap-engage-phase time period elapses during the strap-engage phase, a strap-cut-phase time period elapses during the strap-cut phase, an energy-release-phase time period elapses during the energy-release phase, and a return-phase time period elapses during the return phase. In this example embodiment, the energy-release-phase time period is greater than the return-phase time period even though the third die-assembly angular displacement of the die assembly 610 during the energy-release phase is less than the fourth die-assembly angular displacement of the die assembly 610 during the return phase. Additionally, in this example embodiment, the strap-cut-phase time period is less than the strap-engage-phase time period and greater than the energy-release-phase time period. Also, the strap-engage-phase time period and the return-phase time period are about the same. The second cam 624 has a radially extending lobe 6241 and a cam surface 624s.

The camshaft 620 generally extends through the mounting shaft 390 of the support 300 and is supported by bearings or other suitable components. As best shown in FIGS. 12A-12E, the camshaft 620 is positioned, oriented, and otherwise configured such that the die-assembly biasing element biases the first cam follower 612 of the die assembly 610 into engagement with the cam surface 622s of the first cam 622.

The sealing-assembly gearing 630, which is best shown in FIG. 8, operably connects the transmission assembly 800 and the motor assembly 900 to the camshaft 620 to rotate the camshaft 620 (and the first and second cams 622 and 624 thereon) in the sealing direction S. The sealing-assembly gearing 630 includes a driven gear 632 having teeth 632t, a sun gear (not shown) fixed in rotation with the driven gear 632, a planet-gear carrier 634, multiple planet gears 636, and a ring gear (not shown). The planet gears 636 are rotatably mounted to the planet-gear carrier 634 (such as via respective bearings and mounting pins). The sun gear meshes with and drivingly engages the planet gears 636. The planet gears 636 mesh with the teeth (not shown) of the ring gear, which is fixed in rotation. The splined end 620s of the camshaft 620 is received in an appropriately shaped opening in the planet-gear carrier 634 such that the camshaft 620 and the planet-gear carrier 634 are fixed in rotation. Most components of the sealing-assembly gearing 630 are positioned within the mounting shaft 390 of the support 300 and are supported by bearings or other suitable components.

Generally, in operation, the motor assembly 900 and the transmission assembly 800 drive the driven gear 632 in the sealing direction S, which causes the sun gear to rotate with the driven gear 632 in the sealing direction S. The sun gear drives the planet gears 636. Since the ring gear is fixed in rotation, rotation of the planet gears 636 causes the planet-gear carrier 634 and the camshaft 620 (which is fixed in rotation with the planet-gear carrier 634 via the splined connection) to rotate in the sealing direction S to—via the first and second cams 622 and 624—control the position of the die assembly 610. Accordingly, the sealing-assembly gearing 630 operatively connects the motor assembly 900 and the transmission assembly 800 to the die assembly 610 (via the camshaft 620) to pivot the die assembly 610 (via rotation of the camshaft 620).

More specifically, as noted above, the cam surface 622s of the first cam 622 is divided into four angular sections 622s1, 622s2, 622s3, and 622s4 that correspond to the four phases of the sealing cycle and different positions of the die assembly 610. FIG. 12A shows the first cam 622, the second cam 624, and the die assembly 610 in their respective home positions. When the first cam 622 is in its home position, the first cam follower 612 engages the first cam 622 at the junction between the first and fourth angular sections 622s1 and 622s4 of the cam surface 622s. When the second cam 624 is in its home position, the lobe 6241 engages the second cam follower 613s of the mounting arm 613 of the die assembly 610. The second cam 624 operates with the die-assembly biasing element to retain the die assembly 610 in its home position.

FIG. 12B shows the strapping tool 50 after the strap-engage phase of the sealing cycle has been completed and the motor assembly 900 has rotated the first cam 622 the first cam angular displacement Φ₁in the sealing direction S from its home position to a strap-engaging position. During this rotation, the first angular section 622s1 of the cam surface 622s of the first cam 622 engaged the follower 612, and the sharp increase in the radius of the cam surface 622s from R1 to R2 caused the die assembly 610 to quickly pivot downward the first die-assembly angular displacement such that the dies 614 contact the upper strap portion (not shown for clarity).

FIG. 12C shows the strapping tool 50 after the strap-cut phase of the sealing cycle has been completed and the motor assembly 900 has further rotated the first cam 622 the second cam angular displacement Φ₂in the sealing direction S from its strap-engaging position to a strap-cutting position. During this rotation, the second angular section 622s2 of the cam surface 622s of the first cam 622 engaged the follower 612, and the gradual increase in the radius of the cam surface 622s from R2 to R3 caused the die assembly 610 to slowly pivot downward the second die-assembly angular displacement until the die assembly 610 reached its strap-cutting position, at which point the dies 614 had cooperated with the punch 314 of the support 300 to cut the strap (not shown) and the cutter 616 had cut the strap from the strap supply (not shown). This gradual cutting process (which took longer than the process of lowering the die assembly into contact with the strap) has several benefits over a quick cutting process, including a lower power requirement (leading to more strapping cycles per battery charge) and less strain on the mechanical components of the sealing, transmission, and motor assemblies 600, 800, and 900 (prolonging component life).

When the die assembly 610 is in the sealing position, the die-assembly biasing element, the strap, and other mechanical components of the sealing assembly 600 store significant potential energy that exerts a significant force on the die assembly 610 that attempts to force the die assembly 610 to return to its home position. If this energy is not gradually released, it could cause the first cam 622 to rotate independently of the motor assembly 900 in the sealing rotational direction S far enough that the first cam 622 rotates past its home position. If this were to occur, it would leave the first cam 622 in the wrong position (i.e., any position but its home position) for the next strapping cycle.

The third angular section 622s3 of the cam surface 622s enables this gradual release of the potential energy. FIG. 12D shows the strapping tool 50 after the energy-release phase of the sealing cycle has been completed and the motor assembly 900 has further rotated the first cam 622 the third cam angular displacement Φ₃in the sealing direction S from its strap-cutting position to an energy-releasing position. During this rotation, the third angular section 622s3 of the cam surface 622s of the first cam 622 engaged the follower 612, and the gradual decrease in the radius of the cam surface 622s from R3 to R4 enabled the die-assembly biasing element, the strap, and other mechanical components of the sealing assembly 600 to gradually force the die assembly 610 to pivot upward the third die-assembly angular displacement. This gradual raising of the die assembly 610 (which took about as much time as the cutting process) reduces the force these components exert on the die assembly 610 to a level at which these components cannot rotate the first cam 622 independent of the motor assembly 900.

FIG. 12E shows the strapping tool 50 after the return phase of the sealing cycle has been completed and the motor assembly 900 has further rotated the first cam 622 the fourth cam angular displacement Φ₄in the sealing direction S from its energy-releasing position to its home position. During this rotation, the fourth angular section 622s4 of the cam surface 622s of the first cam 622 engaged the first cam follower 612, and the sharp decrease in radius from R4 to R1 enabled the die-assembly biasing element to quickly force the die assembly 610 to pivot upward the fourth die-assembly angular displacement to its home position. Additionally, during this rotation, the lobe 6241 of the second cam 624 engaged the second cam follower 613f to force the mounting arm 613 and the rest of die assembly 610 upward to its home position.

In other embodiments, the die assembly is vertically movable (rather than pivotable) relative to the support between its home and sealing positions. In these embodiments, the vertical displacement of the die assembly varies during the different phases of the sealing cycle.

Even though a single cam controls the movement of the die assembly through the four phases of the sealing cycle in the above-described embodiment, in other embodiments, multiple cams control the movement of the die assembly through the four phases. For instance, one cam is shaped to engage a cam follower and control movement of the die assembly during the strap-engage and strap-cut phases while different cam is shaped to engage a different cam follower to control movement of the die assembly during the energy-release and return phases.

The transmission assembly 800, which is best shown in FIG. 10, is driven by the motor assembly 900, is operably connected to the tensioning assembly 500 and configured to cause the tension wheel 590 to rotate in the tensioning direction T to tension the strap; and is operably connected to the sealing assembly 600 and configured to cause the camshaft 620 to rotate in the sealing direction S to drive the die assembly 610 to attach the overlapping portions of the strap to one another. The transmission assembly 800 includes a first transmission-gear assembly 810, a second transmission-gear assembly 820, and a connector 830.

The first transmission-gear assembly 810 includes a first driven gear 812 (which is a bevel gear in this example embodiment but may be any suitable gear), a second-gear-assembly drive gear 814 (which is a spur gear in this example embodiment but may be any suitable gear), and a first transmission freewheel 816. The first transmission freewheel 816 is mounted to, engages, and circumscribes the shaft portion 522a of the driven shaft 522 of the tensioning-assembly gearing 510 of the tensioning assembly 500. The first driven gear 812 and the second-gear-assembly drive gear 814 are fixed in rotation with one another (so they rotate together) and are mounted to, engage, and circumscribe the first transmission freewheel 816. The first transmission freewheel 816 is configured to: (1) transmit rotational movement of the first driven gear 812 and the second-gear-assembly drive gear 814 in the tensioning direction T to the driven shaft 522 such that the first driven gear 812, the second-gear-assembly drive gear 814, and the driven shaft 522 rotate together in the tensioning direction T about the tension-wheel rotational axis A590; and (2) not transmit rotational movement of the first driven gear 812 and the second-gear-assembly drive gear 814 in the release direction T_REVto the driven shaft 522 such that the first driven gear 812 and the second-gear-assembly drive gear 814 rotate about the tensioning rotational axis A590 in the release direction T_REVrelative to and around the first transmission freewheel 816 and the driven shaft 522.

The second transmission-gear assembly 820 includes a second driven gear 822 (which is a spur gear in this example embodiment but may be any suitable gear), a second transmission freewheel 824, and a sealing-assembly drive gear 826 (which is a spur gear in this example embodiment but may be any suitable gear) having an elongated shaft. The second transmission freewheel 824 is mounted to, engages, and circumscribes the elongated shaft of the sealing-assembly drive gear 826. The second driven gear 822 is mounted to, engages, and circumscribes the second transmission freewheel 824. The second transmission freewheel 824 is configured to: (1) transmit rotational movement of the second driven gear 822 in a transmission rotational direction TR—referred to herein as the transmission direction TR (FIG. 8)—to the sealing-assembly drive gear 826 such that the second driven gear 822 and the sealing-assembly drive gear 826 rotate together in the transmission direction TR; and (2) not transmit rotational movement of the second driven gear 822 in a rotational direction opposite the transmission direction TR—referred to herein as the non-transmission direction TR_REV(FIG. 8)—to the sealing-assembly drive gear 826 such that the second driven gear 822 rotates in the non-transmission direction TR_REVrelative to and around the second transmission freewheel 824 and the sealing-assembly drive gear 826. Although not shown, the sealing-assembly drive gear 826 is operably connected to the sealing-assembly gearing 630 and configured to drive the sealing-assembly gearing 630 to rotate the camshaft 620 in the sealing direction S.

The connector 830, which is a toothed belt in this example embodiment but may be any suitable connector, operably connects the second-gear-assembly drive gear 814 of the first transmission-gear assembly 810 and the second driven gear 822 of the second transmission-gear assembly 820.

This is merely one example transmission assembly, and the strapping tool may include any suitable transmission assembly or assemblies operably connecting one or more motors to the tensioning and sealing assemblies to drive those assemblies.

The connector 830, which is a toothed belt in this example embodiment but may be any suitable connector, operably connects the second-gear-assembly drive gear 814 of the first transmission-gear assembly 810 and the driven gear 822 of the second transmission-gear assembly 820.

In operation, the motor assembly 900 can drive the first driven gear 812 of the first transmission-gear assembly 810 of the transmission assembly 800 in either the tensioning direction T or the release direction T_REV. When the motor assembly 900 drives the first driven gear 812 in the tensioning direction T, the first driven gear 812, the second-gear-assembly drive gear 814 and the driven shaft 522 rotate together in the tensioning direction T about the tension-wheel rotational axis A₅₉₀. The connector 830 transmits the rotation of the second-gear-assembly drive gear 814 to the second driven gear 822 of the second transmission-gear assembly 820, causing it to rotate in the non-transmission direction TR_REVaround the second transmission freewheel 824, which does not transmit this rotational movement to the sealing-assembly drive gear 826. On the other hand, when the motor assembly 900 drives the first driven gear 812 in the release direction T_REV, the first driven gear 812 and the second-gear-assembly drive gear 814 rotate in the release direction T_REVaround the first transmission freewheel 816, which does not transmit this rotational movement to the driven shaft 522. The connector 830 transmits the rotation of the second-gear-assembly drive gear 814 to the second driven gear 822 of the second transmission-gear assembly 820, causing it to rotate in the transmission direction TR. The second transmission freewheel 824 transmits this rotational movement to the sealing-assembly drive gear 826, which rotates in the transmission direction TR and drives the sealing-assembly gearing 630 to rotate the camshaft 620 in the sealing direction S.

The motor assembly 900, which is best shown in FIGS. 7 and 8, is operably connected to (via the transmission assembly 800) the tensioning assembly 500 and the sealing assembly 600 and is configured to drive those assemblies. The motor assembly 900 includes a motor 910, a drive gear 920, a motor mount 930, and a motor biasing element 940 (though other embodiments may not include the motor-biasing element 940).

As best shown in FIG. 7, the motor 910, which is an electric motor in this example embodiment but may be any suitable motor, includes a motor housing 910b and a rotatable output shaft 910s extending from the motor housing 910b. The drive gear 920, which is a bevel gear in this example embodiment but may be any other suitable gear, is fixedly mounted to the end of the output shaft 910s opposite the motor housing 910b such that the drive gear 920 and the output shaft 910s are fixed in rotation (i.e., rotate together) about a motor rotational axis A910. Specifically, the motor 910 is configured to rotate the output shaft 910s and the drive gear 920 in opposing first and second drive directions D1 and D2 (FIG. 8) to carry out the tensioning and sealing cycles, respectively. The motor mount 930 includes a tubular body 932 and a head 934 at one end of the body 932. The head 934 includes a base 934b and spaced-apart first and second mounting ears 934e1 and 934e2 extending from the base 934b. The body 932 is fixedly mounted to the motor housing 910 (such as via suitable fasteners) such that the output shaft 910s extends through the body 932 and the drive gear 920 is between the mounting ears 934e1 and 934e2. The motor biasing element 940, which is a compression spring in this example embodiment but may be any suitable biasing element, circumscribes the body 932 of the motor mount 930 and is constrained at either end by the motor housing 910b and the base 934b of the head 934 of the motor mount 930.

As shown in FIG. 8, the motor assembly 900 is pivotably mounted at one end to the tensioning assembly 500. The other end of the motor assembly 900 is housed within the motor housing section 130 of the housing 100 of the strapping tool 50 at the other end such that the motor 910 can move relative to the housing 100 and the tensioning assembly 500. The motor assembly 900 is mounted such that the drive gear 920 is meshed with—and therefore configured to drivingly engage—the first driven gear 812 of the first transmission-gear assembly 810 of the transmission assembly 800. The motor assembly 900 is mounted such that, as the tensioning assembly 500 pivots between the strap-tensioning and strap-insertion positions, the motor 910 can move (and in this example embodiment, both pivot and move longitudinally) relative to the housing 100 and the tensioning assembly 500 so the drive gear 920 maintains driving engagement with the first driven gear 812.

Specifically, the first mounting ear 934e1 of the head 934 of the motor housing 930 of the motor assembly 900 is mounted (via a suitable bearing, not labeled) to the driven shaft 522 of the tensioning-assembly gearing 510 of the tensioning assembly 500, and the second mounting ear 934e2 of the head 934 is mounted (via a suitable bearing, not labeled) to the support shaft 512a of the support 512 of the tensioning-assembly gearing 510 such that the motor assembly 900 is pivotable relative to the tensioning assembly 500 about the tension-wheel rotational axis A590. The motor housing section 130 defines one or more internal chambers that house the motor mount 930, the motor 910, and the motor biasing element 940.

The display assembly 1300, which is shown in FIGS. 1A-1C, includes a suitable display screen 1310 with a touch panel 1320. The display screen 1310 is configured to display information regarding the strapping tool 50 (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 1600 to send signals to the controller 1600 and to receive signals from the controller 1600. 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. Certain embodiments of the strapping tool include a separate pushbutton panel instead of a touch panel beneath or integrated with the display screen.

The actuating assembly 1400, which is shown in FIGS. 1A-1C, 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, which is shown in FIG. 1C, 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 910, 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 Wi-Fi, 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 910 to cause the tension wheel 590 to rotate responsive to the first pushbutton actuator 1410 being actuated and maintained in its actuated state. The controller 1600 operates the motor 910 to cause the sealing assembly 600 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 910 to cause the tension wheel 590 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 910 to cause the sealing assembly 600 to carry out the sealing cycle (without requiring additional input from the operator). In the automatic operating mode, the controller 1600 operates the motor 910 to cause the tension wheel 590 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 910 to cause the sealing assembly 600 to carry out the sealing cycle (without requiring additional input from the operator).

The sensors 1700 include any suitable sensors, such as microswitches, optical sensors, ultrasonic sensors, magnetic position sensors, and the like, configured to detect the position of certain components of the strapping tool 50 and to send appropriate signals to the controller 1600. The sensors 1700 may include, for instance: one or more tensioning-assembly-position sensors configured to detect when the tensioning assembly 500 is in its strap-tensioning position and/or its strap-insertion position; one or more camshaft-position sensors configured to detect the rotational position of the camshaft 620 and, specifically, whether the camshaft 620 is in a home rotational position; one or more rocker-lever-position sensors configured to detect when the rocker lever 700 is in its home position, its intermediate position, and/or its actuated position; and one or more actuating assembly sensors configured to detect actuation of the first and second pushbutton actuators 1410 and 1420.

The power supply is electrically connected to (via suitable wiring and other components) and configured to power several components of the strapping tool 50, including the motor 910, the display assembly 1300, the actuating assembly 1400, the controller 1600, and the sensor(s) 1700. The power supply 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 is sized, shaped, and otherwise configured to be received in the receptacle 122 defined by the rear housing section 120 of the housing 100. The strapping tool 50 includes one or more battery-securing devices (not shown) to releasably lock the power supply in place upon receipt in the receptacle. Actuation of a release device of the strapping tool 50 or the power supply unlocks the power supply from the housing 100 and enables an operator to remove the power supply from the receptacle 122.

Use of the strapping tool 50 to carry out a strapping cycle including: (1) a tensioning cycle in which the strapping tool 50 tensions strap around a load; and (2) a sealing cycle in which the strapping tool 50 attaches overlapping upper and lower portions of the strap to one another via a sealless strap joint is described below. Initially, the rocker lever 700 is in its home position, the tensioning assembly 500 is in its strap-tensioning position, and the die assembly 610 is in its home position. The strapping tool 50 is in the automatic mode for the purposes of this example.

The operator pulls the strap leading-end first from a strap supply (not shown), wraps the strap around the load, and positions the leading end of the strap S below another portion of the strap to form upper and lower portions of strap. The operator then pulls the rocker lever 700 from its home position to its actuated position to raise the tensioning assembly 500 from its strap-tensioning position to its strap-insertion position. While holding the rocker lever 700 in its actuated position, the operator introduces the overlapping upper and lower portions of the strap between the punch 314 (on the base 310 of the support 300) and the die 614 (of the die assembly 610 of the sealing assembly 600) and between the tensioning plate 312 (on the base 310 of the support 300) and the tension wheel 590 (of the tensioning assembly 500), as shown in FIG. 3C. The operator then releases the rocker lever 700, which causes various biasing elements to force the rocker lever 700 back to its home position and the tensioning assembly 500 back to its strap-tensioning position. This causes the tension wheel 590 to engage the top surface of the upper portion of strap and force the bottoms surface of the lower portion of strap against the tension plate 312.

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 910 to begin rotating the motor output shaft 910s in the first drive direction D1, which drives the first driven gear 812 of the transmission assembly 800 in the tensioning direction T. As explained in detail above, this causes the tension wheel 590 to begin rotating in the tensioning direction T and pull on the upper portion of the strap, thereby tensioning the strap around the load. Throughout the tensioning cycle, the controller 1600 monitors the current drawn by the motor 910. 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 910, thereby terminating the tensioning cycle.

The controller 1600 then automatically starts the sealing cycle by controlling the motor 910 to begin rotating the motor output shaft 910s in the second drive direction D2, which drives the first driven gear 812 in the release direction T_REV. As explained in detail above, this causes the camshaft 620 and to rotate in the sealing direction S, which pivots the die assembly 610 to its sealing position such that the dies 614 engage the upper portion of strap and force the lower portion of strap against the punch 314 of the base 310 of the support 300, eventually combining to cut keys in the overlapping upper and lower portions of strap. Meanwhile, the cutter 616 of the die assembly 610 cuts the strap from the strap supply. Once the cutter 616 cuts the strap from the strap supply, the upper portion of the strap slides relative to the lower portion of the strap, which causes the keys to interlock and form the sealless strap joint. Continued rotation of the camshaft 620 in the sealing direction S reverses this movement to return the die assembly 610 to its home position. After the sealing cycle is complete, the operator again pulls the rocker lever 700 to raise the tensioning assembly 500 and removes the strapping tool 50 from the tensioned strap loop.

Although the sealing assembly of the above-described example embodiment of the strapping tool comprises a punch and die configured to for a sealless connection in the strap, the sealing assembly may comprise other sealing mechanisms (such as notching jaw assembly, a crimping jaw assembly, a friction-welding assembly, an ultrasonic welding assembly, or a hot-knife assembly) in other embodiments configured to seal any suitable type of strap (such as metal, plastic, or paper strap).

The above-described example embodiment of the strapping tool includes a single motor configured to drive both the tensioning assembly and the sealing assembly. In other embodiments, the strapping tool includes separate motors configured to drive the respective tensioning and sealing assemblies. In these embodiments, either or both motors may be movable relative to the housing of the strapping tool to ensure their respective drive gears remain drivingly engaged to respective driven gears configured to drive the assemblies.

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. In other words, while the strapping tool 50 includes all of the assemblies, components, and features described above, they are independent of one another and may be independently included in other strapping tools.

While the strapping device described above is a handheld strapping tool, the strapping device may be any other suitable strapping device in other embodiments, such as a standalone automatic or semi-automatic strapping machine.

STRAPPING TOOL WITH ENERGY-RELEASE FEATURE

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