Strapping device with a combined tensioning-and-sealing subassembly

Abstract

Various embodiments of the present invention provide a strapping device configured to tension strap around a load and to join two areas of overlapping portions of the strap together via different types of rotation of a tensioning-and-sealing wheel (390). During a tensioning cycle, the tensioning-and-sealing wheel is periodically driven to rotate in one rotational direction to move one of the portions of strap over the other to tension the strap around the load. During a sealing cycle, the tensioning-and-sealing wheel is rotationally oscillated by a wheel actuator (370) in two opposing rotational directions to locally melt two areas of the overlapping strap portions to join them together. The wheel actuator is operably connected to the tensioning-and-sealing wheel via a planetary gearing.

Description

STRAPPING DEVICEWITH A COMBINED TENSIONING- AND-SEALING SUBASSEMBLYPriority

[0001] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 692,339, filed September 9, 2024, the entire contents of which is incorporated herein by reference.Field

[0002] The present disclosure relates to strapping devices, and more particularly to strapping devices configured to tension strap around a load and to attach overlapping layers of the strap to one another via friction welding to form a tensioned strap loop around the load.Background

[0003] Strapping devices are configured to tension strap around a load and to attach overlapping layers of the strap to one another to form a tensioned strap loop around the load. Handheld strapping tools, which can be electrically powered, pneumatically powered, or manually powered, are one common type of strapping device. Certain strapping tools, such as those configured for use with plastic or paper strap, use friction welding to attach overlapping upper and lower strap layers to one another.

[0004] 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 a lower layer of the strap including the leading end of the strap below an upper layer of the strap. The operator introduces the overlapped strap layers into the strapping tool so they extend between a toothed tensioning wheel and a toothed tensioning plate of the strapping tool and between a toothed weld shoe and a toothed weld plate of the strapping tool.The tensioning wheel and plate are typically positioned near the front of the strapping tool, while the weld shoe and plate are positioned rearward of and aligned with the tensioning wheel and plate in the longitudinal direction of the strap. The tensioning wheel is spring-biased to force the strap layers against the tensioning plate, while initially the weld shoe does not contact the strap.

[0005] The operator presses a button to initiate a tensioning cycle during which the tensioning wheel rotates to move the upper strap layer over the lower strap layer and tension the strap around the load. After completion of the tensioning cycle, a sealing cycle is initiated. During the sealing cycle, the weld shoe forces the strap layers against the weld plate. A motor reciprocates the weld shoe at a high frequency as the weld shoe exerts a welding force on the strap layers. The reciprocating weld shoe reciprocates the upper strap layer relative to the lower strap layer, which generates friction between portions of the overlapping strap layers that locally melts them. The motor stops reciprocating the weld shoe while the weld shoe continues to exert the welding force. The melted portions of the overlapping strap layers join and solidify as they cool, thereby attaching the upper and lower strap layers to form the tensioned strap loop.

[0006] Certain known strapping tools that use friction welding to attach the strap layers to one another include separate assemblies — and sometimes even separate motors — for tensioning and sealing the strap. This can make these devices relatively heavy. Since strapping tool operators can use handheld strapping tools hundreds of times each day, there is a need to make the strapping tools as light as possible without sacrificing performance.

[0007] Certain known strapping tools include a base plate that separates the tensioning and weld plates from the load and rests on the load during operation. Since the weld plate is rearward of and aligned with the tensioning plate, the base plate is relatively long. This prevents operators from using the strapping tool to strap curved loads with relatively small radii, such as small bundles of metal pipes, because the length of the base plate prevents the strap from retaining adequate tension after the strapping tool is removed from the load. Since this limits the potential applications of these strapping tools, there is a need for strapping tools with shorter base plates.Summary

[0008] Various embodiments of the present disclosure provide a strapping device configured to tension strap around a load and to join two areas of overlapping portions of the strap together via different types of rotation of a tensioning-and-sealing wheel. During a tensioning cycle, the tensioning-and-sealing wheel is periodically driven to rotate in one rotational direction to move one of the portions of strap over the other to tension the strap around the load. During a sealing cycle, the tensioning-and-sealing wheel is rotationally oscillated in two opposing rotational directions to locally melt two areas of the overlapping strap portions to join them together.Brief Description of the Figures

[0009] Figure 1 is a perspective view of one example embodiment of a strapping tool of the present disclosure.

[0010] Figure 2 is a block diagram of certain components of the strapping tool of Figure 1.

[0011] Figures 3A-3C are diagrammatic views of the strapping tool of Figure 1 securing a load to a pallet.

[0012] Figure 3D is a perspective view of a friction-weld strap joint formed by the strapping tool of Figure 1.

[0013] Figures 4A and 4B are perspective views of the working assembly of the strapping tool of Figure 1.

[0014] Figure 5A is a perspective view of the tensioning-and-sealing subassembly of the working assembly of Figures 4A and 4B.

[0015] Figure 5B is an exploded perspective view of the tensioning-and-sealing subassembly of Figure 5 A.

[0016] Figure 5C is a cross-sectional perspective view of the tensioning-and-sealing subassembly of Figure 5 A taken along line 5C-5C of Figure 5 A.

[0017] Figures 6A-6C are cross-sectional elevational views of the tensioning-and- sealing subassembly of Figure 5 A showing the interaction between the lock of the working assembly of Figures 4A and 4B and the tensioning-and-sealing subassembly.

[0018] Figures 7A-7E are elevational views of the tensioning-and-sealing subassembly of Figures 5A-5C and the tensioning-and-sealing plate of the strapping tool of Figure 1 as the wheel actuator rotationally oscillates and the tensioning-and-sealing wheel rotates during a tensioning cycle.

[0019] Figures 8A-8E are elevational views of the tensioning-and-sealing subassembly of Figures 5A-5C and the tensioning-and-sealing plate of the strapping tool of Figure 1 as the wheel actuator and the tensioning-and-sealing wheel rotationally oscillate during a sealing cycle.

[0020] Figures 9A and 9B are diagrammatical views of a prior art strapping tool and the strapping tool of Figure 1 after strap has been applied to a substantially circular load.

[0021] Figure 10 is a perspective view of another example embodiment of the working assembly of the present disclosure.

[0022] Figure 11 is an exploded perspective view of the working assembly of Figure 10.

[0023] Figures 12A and 12B are cross-sectional elevational views of the working assembly of Figure 10 with the wheel actuator in different rotational positions. The cross-section is taken along line 12A-12A of Figure 10.Detailed Description

[0024] While the systems, devices, and methods described herein may be embodied in various forms, the drawings show and the specification describes certain exemplary and nonlimiting embodiments. Not all of the components shown in the drawings and described in thespecification 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.

[0025] Figures 1A-8E and 9B show one example embodiment of a strapping device of the present disclosure in the form of a battery-powered handheld strapping tool 50 and certain subassemblies and components thereof. As shown in Figures 3A-3C, the strapping tool 50 is configured to carry out a strapping process to tension and seal strap S (plastic 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 layer LL of the strap S (which includes the leading end of the strap S) is positioned below an upper layer UL of the strap S, as shown in Figure 3A. The operator then introduces the overlapped upper and lower layers UL and LL of the strap S into the strapping tool 50 and actuates one or more buttons to initiate the strapping process. As shown in Figure 3B, the strapping tool 50 first carries 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 Figure 3C, the strapping tool 50 carries out a sealing cycle during which the strapping tool 50 connects the upper and lower layers UL and LL of the strap S to one another via friction welding to form a strap joint SJ, as shown in Figure 3D, and cuts the strap S from the strap supply.

[0026] The strapping tool 50 includes a housing 100, a working assembly 150, a pivotable rocker 800 including base plate 810 supporting a tensioning-and-sealing plate 850, a hand lever 900, first and second pushbutton actuators 1410 and 1440, a power supply 1500, and a controller 1600.

[0027] The housing 100, which is shown in Figure 1, is formed from multiple components that collectively at least partially enclose and / or support at least some of the other subassemblies and components of the strapping device 10. In this example embodiment, the housing 100 includes a front housing section that at least partially encloses the working assembly 150, a rear housing section that at least partially encloses and that supports the power supply 1500 and the controller 1600, and a handle extending between and connecting the front and rear housing sections. The operator holds the handle during operation of the strapping device 50. 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.

[0028] The working assembly 150, which is shown in Figures 4A-8E, includes most of the components of the strapping tool 50 that are configured to carry out the strapping process to tension the strap around the load and attach the overlapping layers of the strap to one another. The working assembly 150 includes a first support 210, a cover 220, a second support 230, a tensioning-and-sealing subassembly 300, a lock 500, a transmission 600, and a motor 700.

[0029] The first support 210 serves as a direct or indirect common support for at least some components of the tensioning-and-sealing subassembly 300. As best shown in Figures 5B and 5C, the first support 210 includes an annular wheel-actuator support 212 sized, shaped, and otherwise configured to rotatably support the wheel actuator 370 of the tensioning-and- sealing subassembly 300. The cover 220 is removably attachable to the first support 210 and configured to enclose at least part of certain components of the tensioning-and sealing assembly 300, including the tensioning-and-sealing wheel 390. The second support 230 is attached to thefirst support 210 and serves as a direct or indirect common support for at least some components of the transmission 600 and the motor 700.

[0030] The tensioning-and-sealing subassembly 300 is configured to tension the strap around the load during the tensioning cycle and locally melt overlapping portions of the strap and join them together to form a tensioned strap loop around the load during the sealing cycle via friction welding. The tensioning-and-sealing subassembly 300 includes: an eccentric shaft 310; a driven gear 320; a bushing 325; a freewheel 330; a support 335; a carrier 360; a wheel actuator 370; a set of planet gears 380a, 380b, and 380c rotatably mounted to respective shafts 380al, 380a2, and 380a3; and a tensioning-and-sealing wheel 390.

[0031] The eccentric shaft 310 includes a first shaft portion 312, a second shaft portion 314, an eccentric portion 316, and a third shaft portion 318. The second shaft portion 314 is between the first shaft portion 312 and the eccentric portion 316, and the eccentric portion 316 is between the second shaft portion 314 and the third shaft portion 318. The first, second, and third shaft portions 312, 314, and 318 are cylindrical and share the same central longitudinal axis, which is a shaft axis A310, as best shown in Figures 5B and 5C. The eccentric portion 316 is also cylindrical and has a central longitudinal eccentric axis A316 that is offset from and substantially parallel to the shaft axis A310. In other words, the eccentric portion 316 is radially offset from the shaft axis A310 such that rotation of the eccentric shaft 310 about the shaft axis A310 results in the eccentric axis A316 rotating about the shaft axis A310.

[0032] The driven gear 320, which is a gear pulley in this example embodiment, is fixed in rotation with the first shaft portion 312 via a keyed mounting arrangement at one end (though a splined or other suitable mounting arrangement may be used) such that the driven gear 320 and the eccentric shaft 310 rotate together about the shaft axis A310. The bushing 325 is annular and press fit around the eccentric portion 316. In other embodiments, the bushing comprises a needle bearing or other suitable bearing.

[0033] The carrier 360 includes a disc-shaped tooth carrier 362 having multiple ratchet teeth 362t arranged adjacent to one another around the outer circumference of the toothcarrier 362. The carrier 360 also includes a cylindrical first shaft portion 361 extending in one direction from the center of the tooth carrier 362, a cylindrical second shaft portion 364 extending in the opposite direction from the center of the tooth carrier 362, a sun gear 366 at the end of the second shaft portion 364, and a cylindrical third shaft portion 368 extending from the end of the sun gear 366.

[0034] The wheel actuator 370 includes a generally annular planet-gear carrier 372 and opposing first and second arms 374 and 376 extending from the planet-gear carrier 372. The first and second arms 374 and 376 are spaced apart and parallel (though they could be substantially parallel in other embodiments). The shafts 380al, 380bl, and 380cl of the set of planet gears 380a, 380b, and 380c are mounted to the planet-gear carrier 372. The tensioning- and-sealing wheel 390 includes an annular body 392 having outer teeth 390ot around its outer circumference and inner teeth 390it around its inner circumference.

[0035] The eccentric shaft 310 extends through suitable bores defined through the support 335, the first support 210, and the cover 220 and is rotatably supported by suitable bearings such that the eccentric shaft 310 is rotatable relative to those components about the shaft axis A310. Specifically, the first shaft portion 312 is rotatably supported by a bearing 310b! press fit into a bore in the support 335, the second shaft portion 314 is rotatably supported by a bearing 310b2 press fit into a bore in the first support 210, and the third shaft portion 318 is rotatably supported by a bearing 310b3 press fit into a bore in the cover 220. The bushing 325 is between and engaged by the first and second arms 374 and 376 extending from the planet-gear carrier 372 of the wheel actuator 370.

[0036] The first shaft portion 361 of the carrier 360 extends through and is engaged by the freewheel 330. The freewheel 330 is supported by and positioned within a suitable bore defined through the support 335, which is attached to the first support 210. The freewheel 330 is configured to permit rotation of the carrier 360 about a tensioning-and-sealing axis A390 in a first rotational direction DI (identified in Figures 5B and 5C) and to prevent rotation of the carrier 360 about the tensioning-and-sealing axis A390 in a second rotational direction D2 (identified inFigures 5B and 5C), which is the rotational direction opposite the first rotational direction DI . The second shaft portion 364 of the carrier 360 extends through a bore defined through the wheel-actuator support 212 of the first support 210, and the third shaft portion 368 of the carrier 360 extends through a bore defined through the planet-gear carrier 372 of the wheel actuator 370. Bearings 300b6 and 300b5 support the second and third shaft portions 364 and 368, respectively, such that the carrier 360 is rotatable relative to the first support 210 and the wheel actuator 370 about the tensioning-and-sealing axis A390.

[0037] The wheel actuator 370 is mounted to the wheel -actuator support 212 via a bearing 300b 1 and to the cover 220 via a bearing 300b4 such that the wheel actuator 370 is rotatable relative to the first support 210 and the cover 220 about the tensioning-and-sealing axis A390. The sun gear 366 meshes with the set of planet gears 380a, 380b, and 380c, which in turn mesh with the inner teeth 390it of the tensioning-and-sealing wheel 390. Bearings 300b2 and 300b3 rotatably support the tensioning-and-sealing wheel 390 on the planet-gear carrier 372 of the wheel actuator 370 such that the tensioning-and-sealing wheel 390 is rotatable relative to the wheel actuator 370 about the tensioning-and-sealing axis A390.

[0038] The lock 500, which is best shown in Figures 6A-6C, is configured to enable the carrier 360 to rotate about the tensioning-and-sealing axis A390 in the first rotational direction DI during the tensioning cycle and to prevent the carrier 360 from rotating about the tensioning- and-sealing axis A390 in the first rotational direction DI during the sealing cycle. As explained below, this enables the tensioning-and-sealing subassembly 300 to tension and weld the strap via rotation of the tensioning-and-sealing wheel 390. The lock 500 includes a locking lever 510, a first biasing element 520 having a ball end 525, a second biasing element 540, and a deformer 550.

[0039] The locking lever 510 includes an actuation portion 512 connected to (and here integrally formed with) a pawl 514. The actuation portion 512 has a free end 512a, and the pawl 514 has a free end 514a. The first biasing element 520 is a compression spring in this example embodiment (though it may be any other suitable biasing element in otherembodiments). The second biasing element 540 is a flat leaf spring in this example embodiment (though it may be any other suitable biasing element in other embodiments). The deformer 550 includes a body 552 and a leg 554 extending from the body 552.

[0040] The locking lever 510 is pivotably mounted to the first support 210 via a pin 5 lOp such that the free end 514a of the pawl 514 is adjacent the ratchet teeth 362t of the carrier 360 and such that the free end 512a of the actuation portion 512 is outside the first support 210. The locking lever 510 is pivotable about the pin 51 Op between a locked position (corresponding to a locked configuration of the lock 500) and an unlocked position (corresponding to an unlocked configuration of the lock 500). When the locking lever 510 is in the locked position — as shown in Figures 6 A and 6C — the free end 514a of the pawl 514 engages one of the ratchet teeth 362t of the carrier 360. This engagement prevents the carrier 360 from rotating in the first rotational direction DI (counterclockwise from the perspective shown in Figures 6A-6C). When the locking lever 510 is in the unlocked position — as shown in Figure 6B — the free end 514a of the pawl 514 is disengaged from the ratchet teeth 362t of the carrier 360 and does not prevent the carrier 360 from rotating in the first rotational direction DI. The first biasing element 520 biases the ball end 525 into engagement with the underside of the actuation portion 512 of the locking lever 510 and is positioned to bias the locking lever 510 into the locking position.

[0041] The second biasing element 540 is configured to maintain the locking lever 510 in the unlocked position when the locking lever 510 is moved from the locked position to the unlocked position. The second biasing element 540 is mounted to the first support 210 via a fastener (not labeled) and positioned above the locking lever 510. The second biasing element 540 has a resting configuration and a deformed configuration. The second biasing element 540 is deformable — and in this example embodiment bendable — from the resting configuration to the deformed configuration. When the second biasing element 540 is in the deformed configuration, the second biasing element 540 is biased to return to the resting configuration. Figure 6A shows the second biasing element 540 in the deformed configuration and the locking lever 510 in the locked position. As shown in Figure 6B, when the locking lever 510 is pivoted to the unlockedconfiguration, the second biasing element 540 returns (straightens in this example embodiment) to its resting configuration. When the locking lever 510 is released, the first biasing element 520 forces the actuation portion 512 of the locking lever 510 into engagement with the free end of the second biasing element 540, which prevents the locking lever 510 from pivoting back to the locked position.

[0042] The deformer 550 is configured to deform the second biasing element 540 from the resting configuration to the deformed configuration to enable the first biasing element 520 to force the locking lever 510 to pivot to the locking position. The deformer 550 is pivotably mounted to the first support 210 via a pin 550p such that the deformer 550 is above the locking lever 510 and such that the leg 554 of the deformer 550 is adjacent the second biasing element 540. The deformer 550 is pivotable from a home position to an actuating position to deform the second biasing element 540 from the resting configuration to the deformed configuration. Figures 6A and 6B show the deformer 550 in the home position, and Figure 6C shows the deformer 550 in the actuating position. As shown in Figure 6C, pivoting the deformer 550 from the home position to the actuating position causes the leg 554 to engage and deform the second biasing element 540.

[0043] In operation, rotation of the eccentric shaft 310 about the shaft axis A310 causes rotational oscillation of the wheel actuator 370 about the tensioning-and-sealing axis A390 in the first and second rotational directions DI and D2. Specifically, rotation of the eccentric shaft 310 results in rotation of the eccentric portion 316 and the bushing 325 thereon. As the eccentric shaft 310 — and more particularly, the eccentric portion 316 — rotates, the bushing 325 on the eccentric portion 316 alternately pushes on the first and second arms 374 and 376 of the wheel actuator 370, and these pushing forces cause the wheel actuator 370 to rotationally oscillate about the tensioning-and-sealing axis A390 in the first and second rotational directions DI and D2.

[0044] As described in detail below, when the locking lever 510 is in the unlocked position, this rotational oscillation of the wheel actuator 370 results in the tensioning-and-sealingwheel 390 rotating with the wheel actuator 370 in the second rotational direction and tensioning the strap but not rotating with the wheel actuator 370 in the first rotational direction. When the locking lever is in the locked position, this rotational oscillation of the wheel actuator 370 results in the tensioning-and-sealing wheel 390 rotationally oscillating with the wheel actuator 370 to locally melt the strap to create a strap joint.

[0045] Figures 7A-7E show one complete rotation of the eccentric shaft 310 when the locking lever 510 is in the unlocked position. The outer teeth 390ot of the tensioning-and- sealing wheel 390 engage an upper surface of an upper strap layer UL. The lower surface of the upper strap layer UL engages an upper surface of a lower strap layer LL. The lower surface of the lower strap layer LL engages the teeth of the tensioning-and-sealing plate 850. The tensioning-and-sealing wheel 390 exerts a force against the upper strap layer UL to force it against the lower strap layer LL and in turn forces the lower strap layer LL against the tensioning-and-sealing plate 850.

[0046] As explained above, when the locking lever 510 is in the unlocked position, the carrier 360 and the sun gear 366 are rotatable about the tensioning-and-sealing axis A390 in the first rotational direction DI. The freewheel 330 prevents the carrier 360 and the sun gear 366 from rotating about the tensioning-and-sealing axis A390 in the second rotational direction D2. Initially, as shown in Figure 7A, the eccentric shaft 310 is rotationally positioned such that the tensioning-and-sealing axis A390, the shaft axis A310, and the eccentric axis A316 are coplanar and such that the eccentric axis A316 is between the shaft and tensioning-and-sealing axes A310 and A390. This is the home rotational position of the eccentric shaft 310. The first and second arms 374 and 376 of the wheel actuator 370 are substantially vertical and substantially parallel to the plane containing the three axes. This is the home rotational position of the wheel actuator 370. For clarity, a first point Pl is indicated on the tensioning-and-sealing wheel 390, a second point P2 is indicated on the third shaft portion 368 of the carrier 360, and a third point P3 is indicated on the upper strap layer UL to better show their movement. In the configuration shown in Figure7 A, the first, second, and third points Pl , P2, and P3 are positioned on the plane including the three axes.

[0047] Figure 7B shows the configuration of the components after the eccentric shaft 710 has rotated 90 degrees counter-clockwise about the shaft axis A310. This rotation causes the bushing 325 to force the second arm 376 to move to the right, thereby forcing the wheel actuator 370 to rotate about the tensioning-and-sealing axis A390 in the first rotational direction DI . Since the friction between the tensioning-and-sealing wheel 390 and the upper strap layer UL prevents the tensioning-and-sealing wheel 390 from rotating, the set of planet gears 380a, 380b, and 380c drive the sun gear 366 — and therefore the carrier 360 — to rotate about the tensioning-and-sealing axis A390 in the first rotational direction DI. The angle of rotation a of the carrier 360 may be any suitable angle in other embodiments. Due to the gear ratio between the sun gear 366; the second set of planet gears 380a, 380b, and 380c; and the inner teeth 390it of the tensioning-and- sealing wheel 390, the angle of rotation of the wheel actuator 370 is less than the angle of rotation a of the tensioning-and-sealing wheel 390.

[0048] Figure 7C shows the configuration of the components after the eccentric shaft 310 has rotated 90 degrees counter-clockwise about the shaft axis A310. This rotation causes the bushing 325 to force the first arm 374 to move to the left, thereby forcing the wheel actuator 370 to rotate about the tensioning-and-sealing axis A390 in the second rotational direction D2 back to its home rotational position. Since the freewheel 330 prevents the carrier 360 — and thus the sun gear 366 — from rotating in the second rotational direction D2, the set of planet gears 380a, 380b, and 380c drives the tensioning-and-sealing wheel 390 to rotate about the tensioning-and-sealing axis A390 in the second rotational direction D2. As the tensioning-and-sealing wheel 390 rotates in the second rotational direction D2, it exerts a force on the upper strap layer UL in a second longitudinal direction L2 (opposite a first longitudinal direction LI) that causes the upper strap layer UL to slide over the lower strap layer LL in the second longitudinal direction L2 as shown by the new position of the third point P3. The angle of rotation 0 of the tensioning-and-sealing wheel 390 may be any suitable angle. Due to the gear ratio between the sun gear 366; the secondset of planet gears 380a, 380b, and 380c; and the inner teeth 390it of the tensioning-and-sealing wheel 390, the angle of rotation of the wheel actuator 370 is less than the angle of rotation 0 of the tensioning-and-sealing wheel 390.

[0049] Figure 7D shows the configuration of the components after the eccentric shaft 310 has rotated another 90 degrees counter-clockwise about the shaft axis A310. This rotation causes the bushing 325 to force the second arm 376 to move to the left, thereby forcing the wheel actuator 370 to rotate about the tensioning-and-sealing axis A39oin the second rotational direction D2. As explained above with respect to Figure 7C, this causes the second set of planet gears 380a, 380b, and 380c to drive the tensioning-and-sealing wheel 390 to rotate about the tensioning-and-sealing axis A390 in the second rotational direction D2. As the tensioning-and- sealing wheel 390 rotates in the second rotational direction D2, it exerts a force on the upper strap layer UL in the second longitudinal direction L2 that causes the upper strap layer UL to slide over the lower strap layer LL in the second longitudinal direction L2. The tensioning-and- sealing wheel 390 rotates the angle of rotation 0.

[0050] Figure 7E shows the configuration of the components after the eccentric shaft 310 has rotated another 90 degrees counter-clockwise about the shaft axis A490 to return to its home rotational position. This rotation causes the bushing 325 to force the first arm 374 to move to the right, thereby forcing the wheel actuator 370 to rotate about the tensioning-and-sealing axis A390 in the first rotational direction DI back to its home rotational position. As explained above with respect to Figure 7B, this causes the second set of planet gears 380a, 380b, and 380c to drive the sun gear 366 and thus the carrier 360 to rotate about the tensioning-and-sealing axis A390 in the first rotational direction DI. Although not shown in Figure 7E, the carrier 360 rotates the angle of rotation a.

[0051] Accordingly, with the locking lever 510 in the unlocked position: (a) when the eccentric shaft 310 drives the wheel actuator 390 to rotate in the first rotational direction DI, the set of planetary gears 380a, 380b, and 380c drive the sun gear 366 in the first rotational direction DI; and (b) when the eccentric shaft 310 drives the wheel actuator 390 to rotate in thesecond rotational direction D2, the set of planetary gears 380a, 380b, and 380c drive the tensioning-and-sealing wheel 390 in the second rotational direction D2. Put differently, the eccentric shaft 310 is operably connected to the sun gear 366 and to the tensioning-and-sealing wheel 390 and configured to alternately drive the sun gear 366 in the first rotational direction DI and the tensioning-and-sealing wheel 390 in the second rotational direction D2. So as the eccentric shaft 310 continuously rotates in one rotational direction, the tensioning-and-sealing wheel 390 is periodically — not continuously — driven in the second rotational direction to apply tension to the upper strap layer UL. As used herein, the tensioning-and-sealing wheel 390 is “periodically driven” when it is driven multiple times with a break in between each instance of driving during which the tensioning-and-sealing wheel 390 is not driven. In certain embodiments, the length of the breaks between consecutive instances of driving is the same or substantially the same while the tensioning-and-sealing wheel is periodically driven. In other embodiments, the length of the breaks between consecutive instances of driving differs while the tensioning-and-sealing wheel is periodically drive (e.g., the breaks become longer as the tension in the strap increases), during the periodic driving.

[0052] Figures 8A-8E show one complete rotation of the eccentric shaft 310 when the locking lever 510 is in the locked position. The outer teeth 390ot of the tensioning-and- sealing wheel 390 engage an upper surface of an upper strap layer UL. The lower surface of the upper strap layer UL engages an upper surface of a lower strap layer LL. The lower surface of the lower strap layer LL engages the teeth of the tensioning-and-sealing plate 850. The tensioning-and-sealing wheel 390 exerts a force against the upper strap layer UL to force it against the lower strap layer LL and in turn forces the lower strap layer LL against the tensioning-and-sealing plate 850.

[0053] As explained above, when the locking lever 510 is in the locked position, the carrier 360 and the sun gear 366 are prevented from rotating about the tensioning-and-sealing axis A390 in the first rotational direction DI. The freewheel 330 prevents the carrier 360 and the sun gear 366 from rotating about the tensioning-and-sealing axis A390 in the second rotationaldirection D2. Thus, when the locking lever 510 is in the locked position, the carrier 360 is prevented from rotating about the tensioning-and-sealing axis A390.

[0054] Initially, as shown in Figure 8 A, the eccentric shaft 310 is rotationally positioned such that the tensioning-and-sealing axis A390, the shaft axis A310, and the eccentric axis A316 are coplanar and such that the eccentric axis A316 is between the shaft and tensioning- and-sealing axes A310 and A390. This is the home rotational position of the eccentric shaft 310. The first and second arms 374 and 376 of the wheel actuator 370 are substantially vertical and substantially parallel to the plane containing the three axes. This is the home rotational position of the wheel actuator 370. For clarity, a first point Pl is indicated on the tensioning-and-sealing wheel 390 and a second point P2 is indicated on the third shaft portion 368 of the carrier 360 to better show their rotational movement. In the configuration shown in Figure 8A, the first point Pl is positioned on the plane including the three axes.

[0055] Figure 8B shows the configuration of the components after the eccentric shaft 310 has rotated 90 degrees counter-clockwise about the shaft axis A310. This rotation causes the bushing 325 to force the second arm 376 to move to the right, thereby forcing the wheel actuator 370 to rotate about the tensioning-and-sealing axis A390 in the first rotational direction DI. Since the carrier 360 — and specifically the sun gear 366 of the carrier 360 — is prevented from rotating about the tensioning-and-sealing axis A390, the set of planet gears 380a, 380b, and 380c drive the tensioning-and-sealing wheel 390 to rotate about the tensioning-and-sealing axis A390 in the first rotational direction DI. As the tensioning-and-sealing wheel 390 rotates in the first rotational direction DI, it exerts a force on the upper strap layer UL in a first longitudinal direction LI that causes the upper strap layer UL to slide over the lower strap layer LL in the first longitudinal direction LL The angle of rotation 0 of the tensioning-and-sealing wheel 390 may be any suitable angle. Due to the gear ratio between the sun gear 366; the second set of planet gears 380a, 380b, and 380c; and the inner teeth 390it of the tensioning-and-sealing wheel 390, the angle of rotation of the wheel actuator 370 is less than the angle of rotation 0 of the tensioning- and-sealing wheel 390.

[0056] Figure 8C shows the configuration of the components after the eccentric shaft 310 has rotated 90 degrees counter-clockwise about the shaft axis A310. This rotation causes the bushing 325 to force the first arm 374 to move to the left, thereby forcing the wheel actuator 370 to rotate about the tensioning-and-sealing axis A390 in the second rotational direction D2 back to its home rotational position. Since the carrier 360 — and specifically the sun gear 366 of the carrier 360 — is prevented from rotating about the tensioning-and-sealing axis A390, the set of planet gears 380a, 380b, and 380c drive the tensioning-and-sealing wheel 390 to rotate about the tensioning-and-sealing axis A390 in the second rotational direction D2. As the tensioning-and- sealing wheel 390 rotates in the second rotational direction D2, it exerts a force on the upper strap layer UL in a second longitudinal direction L2 (opposite the first longitudinal direction LI) that causes the upper strap layer UL to slide over the lower strap layer LL in the second longitudinal direction L2. Although not shown in Figure 8C, the tensioning-and-sealing wheel 390 rotates the angle of rotation 0 back to its home rotational position.

[0057] Figure 8D shows the configuration of the components after the eccentric shaft 310 has rotated another 90 degrees counter-clockwise about the shaft axis A310. This rotation causes the bushing 325 to force the second arm 376 to move to the left, thereby forcing the wheel actuator 370 to rotate about the tensioning-and-sealing axis A390 in the second rotational direction D2. As explained above, this causes the second set of planet gears 380a, 380b, and 380c to drive the tensioning-and-sealing wheel 390 to rotate about the tensioning-and-sealing axis A390 in the second rotational direction D2. As the tensioning-and-sealing wheel 390 rotates in the second rotational direction D2, it exerts a force on the upper strap layer UL in the second longitudinal direction L2 that causes the upper strap layer UL to slide over the lower strap layer LL in the second longitudinal direction L2. The tensioning-and-sealing wheel 390 rotates the angle of rotation 9.

[0058] Figure 8E shows the configuration of the components after the eccentric shaft 310 has rotated another 90 degrees counter-clockwise about the shaft axis A310 to return to its home rotational position. This rotation causes the bushing 325 to force the first arm 374 to moveto the right, thereby forcing the wheel actuator 370 to rotate about the tensioning-and-sealing axis A390 in the first rotational direction DI back to its home rotational position. As explained above, this causes the second set of planet gears 380a, 380b, and 380c to drive the tensioning- and-sealing wheel 390 to rotate about the tensioning-and-sealing axis A390 in the first rotational direction DI. As the tensioning-and-sealing wheel 390 rotates in the first rotational direction DI, it exerts a force on the upper strap layer UL in the first longitudinal direction LI that causes the upper strap layer UL to slide over the lower strap layer LL in the first longitudinal direction LI. Although not shown in Figure 9E, the tensioning-and-sealing wheel 390 rotates the angle of rotation 9 back to the home position.

[0059] Accordingly, with the locking lever 510 in the locked position, rotation of the eccentric shaft 310 drives the wheel actuator 390 to rotationally oscillate about the tensioning- and-sealing axis A390 by an angle of rotation 0. This rotational oscillation is caused by the eccentric shaft 310 forcing the wheel actuator 370 to rotationally oscillate about the tensioning- and-sealing axis A390 by an angle of rotation less than 0. As explained above, rotational oscillation of the tensioning-and-sealing wheel 390 results in reciprocation of the upper strap layer UL over the lower strap layer LL. The combination of the downward pressure the tensioning-and-sealing wheel 390 exerts on the strap and the rapid reciprocation of the tensioning-and-sealing wheel 390 locally melts the portions of the upper and lower strap layers UL and LL together to form a strap joint when cooled. So as the eccentric shaft 310 continuously rotates in one rotational direction, the tensioning-and-sealing wheel 390 is continuously rotationally oscillated to move the upper strap layer UL back and forth longitudinally relative to the lower strap layer LL.

[0060] The motor 700, which is best shown in Figures 2, 4A, and 4B, is mounted to the second support 230 and includes a rotatable output shaft (not shown). The motor 700 is configured to rotate the output shaft to carry out the tensioning and sealing cycles as explained below. The motor 700 includes an electric motor in this example embodiment but may include any suitable motor or other actuator in other embodiments.

[0061] The transmission 600, which is best shown in Figures 4A and 4B, is driven by the motor 700 and is operably connected to the tensioning-and-sealing subassembly 300 and configured to cause the tensioning-and-sealing subassembly 300 to: (1) tension the strap around the load during the tensioning cycle by periodically driving the tensioning-and-sealing wheel 390 about the tensioning-and-sealing axis A390 in the second rotational direction D2; and (2) locally melt the strap via friction welding during the sealing cycle by rotationally oscillating the tensioning-and-sealing wheel 390 about the tensioning-and-sealing axis A390 in the first and second rotational directions DI and D2. To do so, the transmission 600 is configured to transmit output from the motor 700 to the eccentric shaft 310 when the motor 700 rotates the output shaft. The transmission 600 includes a transmission shaft 610, a gear pulley 620, and a belt 620b. The transmission shaft 610 is coupled to and rotatable with the output shaft of the motor 700. The tensioning gear pulley 620 is mounted to and fixed in rotation with the transmission shaft 610. The belt 620b operably connects the gear pulley 620 to the driven gear 320.

[0062] The rocker 800 is pivotable relative to the tensioning-and-sealing subassembly 300 between a tensioning-and-sealing position shown in Figures 7A-8E and a strap-insertion position. The tensioning-and-sealing plate 850 is adjacent to the tensioning-and- sealing wheel 390 when the rocker 800 is in the tensioning-and-sealing position and is further spaced from the tensioning-and-sealing wheel 390 when the rocker is in the strap-insertion position. The hand lever 900 is operably connected to the rocker 800 and actuatable to pivot the rocker 800 from the tensioning-and-sealing position to the strap-insertion position. A suitable biasing element, such as a compression spring, biases the rocker 800 to the tensioning-and- sealing position.

[0063] The controller 1600, which is shown in Figure 2, 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 specialpurpose processor, a digital-signal processor, one or more microprocessors, one or moremicroprocessors in association with a digital -sign al processor core, one or more applicationspecific 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 700. 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.

[0064] 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 700 and the controller 1600. 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.

[0065] Use of the strapping tool 50 to carry out a strapping process including a tensioning cycle in which the strapping tool 50 tensions strap around a load and a sealing cycle in which the strapping tool 50 attaches overlapping upper and lower strap layers to one another via friction welding to form a strap joint is described below. Initially, the locking lever 510 of the lock 500 is in its locked position and the second biasing element 540 is in its deformed configuration, as shown in Figure 6A.

[0066] The operator pulls the strap S leading-end first from a strap supply, wraps the strap around the load, and positions a lower strap layer LL — which includes the leading end of the strap S — below an upper strap layer UL. The operator pulls the hand lever 900 to pivot the rocker 800 to the strap-insertion position. While continuing to pull the hand lever 900, theoperator introduces the overlapping upper and lower strap layers UL and LL between the tensioning-and-sealing wheel 390 and the tensioning-and-sealing plate 850 and then releases the hand lever 900, which enables suitable biasing elements to force the tensioning-and-sealing plate 850 to its tensioning-and-sealing position. Eventually, the outer teeth 390ot of the tensioning- and-sealing wheel 390 engage the upper surface of the upper strap layer UL and force the bottom surface of the lower strap layer LL against the toothed surface of the tensioning-and-sealing plate 850, as shown in Figure 7A.

[0067] The operator then actuates the first pushbutton actuator 1410 to initiate the tensioning cycle and holds the first pushbutton actuator 1410 in the actuated position. In this example embodiment, the first pushbutton actuator 1410 is operably connected to the locking lever 510 such that actuation of the first pushbutton actuator 1410 results in movement of the locking lever 510 from the locked position to the unlocked position. Accordingly, as shown in Figure 6B, the operator actuating the first pushbutton actuator results in the locking lever 510 moving from the locked position to the unlocked position and the second biasing element 540 returning to its resting configuration. In response to the operator actuating the first pushbutton actuator 1410, the controller 1600 starts the tensioning cycle by controlling the motor 700 to begin rotating the output shaft. As explained above, the transmission 600 transmits this rotational movement to the eccentric shaft 310 of the tensioning-and-sealing subassembly 300, which in turn causes the tensioning-and-sealing wheel 390 to periodically rotate in the second rotational direction D2 as explained above in connection with Figures 7A-7E. As the tensioning-and- sealing wheel 390 is periodically driven, it pulls the upper strap layer UL of the strap over the lower strap layer LL, thereby tensioning the strap around the load. When the operator releases the first pushbutton actuator 1410 — or when the current drawn by the motor 700 reaches a preset value that is correlated with a preset desired strap tension for this strapping process (depending on the embodiment) — the controller 1600 stops the motor 700, thereby completing the tensioning cycle.

[0068] The operator then actuates the second pushbutton actuator 1440 to initiate the sealing cycle. In this example embodiment, the second pushbutton actuator 1440 is operably connected to the deformer 550 such that actuation of the second pushbutton actuator 1440 results in movement of the deformer 550 from the home position to the actuating position. As explained above with respect to Figure 6C, this deforms the second biasing element 540 from the resting configuration to the deformed configuration such that the first biasing element 520 forces the locking lever 510 back to the locked position. In response to the operator actuating the second pushbutton actuator 1440, the controller 1600 starts the sealing cycle by controlling the motor 700 to begin rotating the output shaft. As explained in detail above, the transmission 600 transmits this rotational movement to the eccentric shaft 310 of the tensioning-and-sealing subassembly 300, which in turn causes the tensioning-and-sealing wheel 390 to rotationally oscillate in the first and second rotational directions DI and D2 as explained above in connection with Figures 8A-8E. The combination of the downward pressure the tensioning-and-sealing wheel 390 exerts on the strap S and the rapid rotational oscillation of the tensioning-and-sealing wheel 390 locally melts the portions of the upper and lower strap layers UL and LL together. After a preset period or a preset quantity of rotations of the output shaft, the controller 1600 controls the motor 700 to stop rotating the output shaft, completing the sealing cycle. The melted portions of the overlapping strap layers join and solidify as they cool, thereby attaching the upper and lower strap layers to form the strap joint and the tensioned strap loop.

[0069] The strapping tool of the present disclosure solves the above problems. First, using rotation of the tensioning-and-sealing wheel to tension the strap and to form the strap joint strap eliminates the need for separate tensioning and welding assemblies (and in some embodiments separate tensioning and welding motors), which renders the tool lighter and easier to use for prolonged periods of time compared to traditional strapping tools with distinct assemblies. Second, elimination of the separate welding assembly enables the base plate of the tool to be shorter in the longitudinal direction than the plates of traditional strapping tools, which enables the strapping tool of the present disclosure to be used for more applications (such as tostrap curved loads with relatively small radii) than many traditional strapping tools. This is illustrated in Figures 9 A and 9B. Figure 9A shows a relatively long prior art base plate BP above which a tensioning wheel TW and welder W are positioned. Figure 9B shows the relatively short base plate 810 of the present disclosure above which the tensioning-and-sealing wheel 390 of the present disclosure is positioned. When used to strap identical circular loads L with strap S, more tension will be retained in the strap after removal of the base plate when the shorter base plate of the present disclosure is used.

[0070] Figures 10-12B show another embodiment of the working assembly 2150 of the present disclosure. The working assembly 2150 includes a support 2210, a cover 2220, a tensioning-and-sealing subassembly 2300, a locking lever 2500, a transmission (not shown), and a motor (not shown).

[0071] The support 2210 serves as a direct or indirect common support for at least some components of the tensioning-and-sealing subassembly 2300 and the locking lever 2500. As best shown in Figure 11, the support 2210 includes an annular wheel-actuator support 2210 sized, shaped, and otherwise configured to rotatably support the wheel actuator 2370 of the tensioning-and-sealing subassembly 2300. The cover 2220 is attached to the support 2210 and at least partially encloses certain components of the working assembly 2150, such as the tensioning-and-sealing wheel 2390.

[0072] The tensioning-and-sealing subassembly 2300 is configured to tension the strap around the load during the tensioning cycle and locally melt overlapping portions of the strap and join them together to form a tensioned strap loop around the load during the sealing cycle via friction welding. The tensioning-and-sealing subassembly 2300 includes: an eccentric shaft 2310; a pivoter 2340; a freewheel 2330; a support 2335; a carrier 360; a wheel actuator 2370; a set of planet gears 2380a, 2380b, and 2380c rotatably mounted to respective shafts 2380al, 2380a2, and 2380a3; and a tensioning-and-sealing wheel 2390.

[0073] The eccentric shaft 2310 includes a first shaft portion 2312, a second shaft portion 2314, and an eccentric portion 2316. The second shaft portion 2314 is between the firstshaft portion 2312 and the eccentric portion 2316. The first and second shaft portions 2312 and 314 are substantially cylindrical and share the same central longitudinal axis, which is a shaft axis A2310, as best shown in Figures 11-12B. The eccentric portion 2316 is also cylindrical and has a central longitudinal eccentric axis A2316 that is offset from and substantially parallel to the shaft axis A2310. In other words, the eccentric portion 2316 is radially offset from the shaft axis A2310 such that rotation of the eccentric shaft 2310 about the shaft axis A2310 results in the eccentric axis A2316 rotating about the shaft axis A2310.

[0074] The pivoter 2340 is annular and includes a radial bore sized and shaped to receive part of the eccentric portion 2316 of the eccentric shaft 2310.

[0075] The carrier 2360 includes a disc-shaped tooth carrier 2362 having multiple ratchet teeth 2362t arranged adjacent to one another around the outer circumference of the tooth carrier 2362. The carrier 2360 also includes a cylindrical first shaft portion 2361 extending in one direction from the center of the tooth carrier 2362, a cylindrical second shaft portion 2364 extending in the opposite direction from the center of the tooth carrier 2362, a sun gear 2366 at the end of the second shaft portion 2364, and a cylindrical third shaft portion 2368 extending from the end of the sun gear 2366.

[0076] The wheel actuator 2370 includes a generally annular planet-gear carrier 2372 and opposing first and second arms 2374 and 2376 extending from the planet-gear carrier 2372. The first and second arms 2374 and 2376 are spaced apart and substantially parallel. The pivoter 2340 is positioned between and held by the ends of the first and second arms 2374 and 2376 such that the pivoter 2340 is rotatable about its central longitudinal axis. The shafts 2380al, 2380b 1, and 2380c 1 of the set of planet gears 2380a, 2380b, and 2380c are mounted to the planet-gear carrier 2372. The tensioning-and-sealing wheel 2390 includes an annular body 2392 having outer teeth 2390ot around its outer circumference and inner teeth 2390it around its inner circumference.

[0077] The eccentric shaft 2310 extends through suitable bores defined through the support 2210 and is rotatably supported by suitable bearings such that the eccentric shaft 310 isrotatable relative to the support 2210 about the shaft axis A2310. Specifically, the first shaft portion 2312 is rotatably supported by a bearing 2310b 1 press fit into a bore in the support 2210 and the second shaft portion 2314 is rotatably supported by a bearing 2310b2 press fit into a bore in the support 2210. The eccentric portion 2316 is at least partially received in the radial bore of the pivoter 2340, as shown in Figures 12A and 12B

[0078] The first shaft portion 2361 of the carrier 2360 extends through and is engaged by the freewheel 2330. The freewheel 2330 is supported by and positioned within a suitable bore defined through the support 2335, which is attached to the support 2210. The freewheel 2330 is configured to permit rotation of the carrier 2360 about a tensioning-and- sealing axis A2390 in a first rotational direction and to prevent rotation of the carrier 2360 about the tensioning-and-sealing axis A2390 in a second rotational direction, which is the rotational direction opposite the first rotational direction DI. The second shaft portion 2364 of the carrier 2360 extends through a bore defined through the wheel-actuator support 2212 of the support 2210, and the third shaft portion 2368 of the carrier 2360 extends through a bore defined through the planet-gear carrier 2372 of the wheel actuator 2370. Suitable bearings support the second and third shaft portions 2364 and 2368, respectively, such that the carrier 2360 is rotatable relative to the support 2210 and the wheel actuator 2370 about the tensioning-and-sealing axis A2390.

[0079] The wheel actuator 2370 is mounted to the wheel-actuator support 2212 and to the cover 2220 via suitable bearings such that the wheel actuator 2370 is rotatable relative to the support 2210 and the cover 2220 about the tensioning-and-sealing axis A2390. The sun gear 2366 meshes with the set of planet gears 2380a, 2380b, and 2380c, which in turn mesh with the inner teeth 2390it of the tensioning-and-sealing wheel 2390. Suitable bearings rotatably support the tensioning-and-sealing wheel 2390 on the planet-gear carrier 2372 of the wheel actuator 2370 such that the tensioning-and-sealing wheel 2390 is rotatable relative to the wheel actuator 2370 about the tensioning-and-sealing axis A2390.

[0080] The locking lever 2500, which is best shown in Figures 6A-6C, is pivotably mounted to the support 2210 via a suitable pivot pin. Similar to the locking lever 510 describedabove, the locking lever 2500 has a locked position in which the locking lever 2500 engages one of the ratchet teeth 2362t of the carrier 2360 to prevent the carrier 2360 from rotating in the first rotational direction and an unlocked position in which the locking lever 2500 is removed from the ratchet teeth 2362t and does not prevent the carrier 2360 from rotating in the first rotational direction.

[0081] In operation, rotation of the eccentric shaft 2310 about the shaft axis A2310 causes rotational oscillation of the wheel actuator 2370 about the tensioning-and-sealing axis A239o in the first and second rotational directions DI and D2. Specifically, rotation of the eccentric shaft 2310 results in rotation of the eccentric portion 2316. As the eccentric shaft 2310 — and more particularly, the eccentric portion 2316 — rotates, the eccentric portion 2316 imposes alternating upward and downward forces on the pivoter 2340, which in turn imposes alternating upward and downward forces on the arms 2374 and 2376 of the wheel actuator 2370, and these forces cause the wheel actuator 2370 to rotationally oscillate about the tensioning-and- sealing axis A2390 in the first and second rotational directions. Figure 12A shows the eccentric portion 2316, the first arm 2374, and the second arm 2376 at their lowermost positions, and Figure 12B shows them at their uppermost position. Although not repeated for brevity, this rotational oscillation of the wheel actuator 2370 is used to tension the strap around the load and to join two overlapping portions of strap to one another depending on the position of the locking lever 2500.

[0082] In other embodiments, the tensioning-and-sealing subassembly includes a rotation preventer. The rotation preventer has a first configuration in which it is operably connected to the tensioning-and-sealing wheel and configured to prevent rotation of the tensioning-and-sealing wheel in the first rotational direction and a second configuration in which it is not operably connected to the tensioning-and-sealing wheel and not configured to prevent rotation of the tensioning-and-sealing wheel in the first rotational direction. In these embodiments, the rotation preventer is in the first configuration when the locking lever is in the unlocked position to facilitate carrying out the tensioning cycle and in the second configurationwhen the locking lever is in the locked position to facilitate carrying out the sealing cycle. In certain embodiments, the locking lever is operably connected to the rotation preventer to move it between the first and second configurations as the locking lever moves between the unlocked and locked positions. The rotation preventer may include any suitable components, such as a freewheel or a ratchet-pawl mechanism.

[0083] In certain embodiments, the tensioning-and-sealing subassembly is movable (such as liftable) relative to the tensioning-and-sealing plate.

[0084] 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.

[0085] In the example embodiments described above, the working assembly is employed as part of a portable handheld strapping tool. The working assembly may be incorporated into any other type of strapping device, such as a general-purpose strapping machine or the strapping head of a special -purpose strapping machine.

Claims

Claims1. A strapping device comprising: a tensioning-and-sealing plate; a tensioning-and-sealing wheel adjacent to the tensioning-and-sealing plate and rotatable about a first axis in opposing first and second rotational directions; a wheel actuator; a lock having a first configuration and a second configuration; a motor operably connected to the wheel actuator and configured to cause the wheel actuator to rotationally oscillate in the first and second rotational directions; and gearing operably connecting the wheel actuator to the tensioning-and-sealing wheel and configured such that, when opposing first and second strap portions are positioned between the tensioning-and-sealing wheel and the tensioning-and-sealing plate: when the lock is in the first configuration and the wheel actuator rotationally oscillates, the gearing periodically drives the tensioning-and-sealing wheel to rotate about the first axis in the second rotational direction; and when the lock is in the second configuration and the wheel actuator rotationally oscillates, the gearing drives the tensioning-and-sealing wheel to rotationally oscillate about the first axis in the first and second rotational directions.

2. The strapping device of claim 1, wherein when the opposing first and second strap portions are positioned between the tensioning-and-sealing wheel and the tensioning-and-sealing plate, when the lock is in the first configuration and the wheel actuator rotationally oscillates, the gearing is configured to periodically drive the tensioning-and-sealing wheel to rotate about the first axis in the second rotational direction without driving the tensioning-and-sealing wheel to rotate about the first axis in the first rotational direction.

3. The strapping device of claim 1, wherein the gearing comprises a sun gear and multiple planet gears meshed with the sun gear, wherein the tensioning-and-sealing wheel comprises inner teeth meshed with the planet gears.

4. The strapping device of claim 3, wherein when the lock is in the first configuration, the lock does not prevent the sun gear from rotating in the first rotational direction, and wherein when the lock is in the second configuration, the lock prevents the sun gear from rotating in the first rotational direction.

5. The strapping device of claim 4, wherein when the lock is in the first configuration and the wheel actuator rotates in the first rotational direction, the planet gears drive the sun gear to rotate in the first rotational direction, and wherein when the lock is in the second configuration and the wheel actuator rotates in the second rotational direction, the planet gears drive the tensioning-and-sealing wheel to rotate about the first axis in the second rotational direction.

6. The strapping device of claim 5, further comprising a rotation preventer configured to prevent rotation of the sun gear in the second rotational direction.

7. The strapping device of claim 6, wherein the device comprises a freewheel.

8. The strapping device of claim 6, further comprising a carrier comprising the sun gear and a plurality of circumferentially spaced ratchet teeth, wherein the lock comprises: a locking lever comprising a pawl, wherein the locking lever is pivotable relative to the ratchet teeth between a locked position in which the pawl is positioned to engage one of the ratchet teeth and prevent the sun gear from rotating in the first rotational direction and an unlocked position in which the pawl is positioned not to engage the ratchet teeth and not prevent the sun gear from rotating in the first rotational direction; and a biasing element biasing the locking lever to the locked position.

9. The strapping device of claim 8, wherein the wheel actuator comprises a planetgear carrier to which the planet gears are mounted.

10. The strapping device of claim 1, further comprising an eccentric shaft rotatable about a second axis, wherein the eccentric shaft comprises an eccentric portion radially offset from the second axis, wherein the eccentric shaft operably connects the motor to the wheelactuator such that rotation of the eccentric shaft about the second axis causes the eccentric portion to cause the wheel actuator to rotationally oscillate.

11. The strapping device of claim 10, wherein the motor is operably connected to the eccentric shaft and configured to rotate the eccentric shaft about the second axis.

12. The strapping device of claim 11, wherein the wheel actuator comprises a body and first and second arms extending from the body and spaced-apart from one another, wherein the eccentric portion of the eccentric shaft is between the first and second arms.

13. The strapping device of claim 11, further comprising a controller operably connected to the motor and configured to control the motor to rotate the eccentric shaft.

14. The strapping device of claim 13, wherein the controller is operably connected to the motor and configured to control the motor to rotate the eccentric shaft responsive to receipt of a first user input resulting in movement of the lock to the first configuration.

15. The strapping device of claim 14, wherein the controller is operably connected to the motor and configured to control the motor to rotate the eccentric shaft responsive to receipt of a second user input resulting in movement of the lock to the second configuration.

16. The strapping device of claim 15, wherein the controller is operably connected to the motor and configured to control the motor to rotate the eccentric shaft in the same rotational direction responsive to receipt of the first user input and the second user input.

17. A method of operating a strapping device, the method comprising: encircling a load with a strap; positioning overlapping first and second portions of the strap between a tensioning-and- sealing wheel and a tensioning-and-sealing plate, wherein the tensioning-and-sealing wheel is rotatable about a first axis in opposing first and second rotational directions;periodically driving the tensioning-and-sealing wheel to rotate in the second rotational direction to move the first portion of the strap over the second portion of the strap to tension the strap around the load; and rotationally oscillating the tensioning-and-sealing wheel in the first and second rotational directions to join two overlapping portions of the strap together.

18. The method of claim 17, wherein periodically driving the tensioning-and-sealing wheel in the second rotational direction comprises doing so without driving the tensioning-and- sealing wheel in the first rotational direction.

19. The method of claim 17, further comprising rotationally oscillating a wheel actuator operably connected to the tensioning-and-sealing wheel via gearing while a lock is in a first configuration to periodically drive the tensioning-and-sealing wheel to rotate in the second rotational direction.

20. The method of claim 19, further comprising rotationally oscillating the wheel actuator while the lock is in a second configuration to rotationally oscillate the tensioning-and- sealing wheel in the first and second rotational directions.

Images