Strapping device

Abstract

Various embodiments of the present disclosure provide a strapping device including a weld plate; a motor; a weld arm comprising a weld pad and movable between a weld-arm home position and a sealing position; a link movable from a first position to a second position to cause the weld arm to move from the weld-arm home position to the sealing position; a cam engager supported by the link and movable between a cam-engager home position and an actuated position; and a cam configured such that rotation of the cam in one direction causes the cam engager to move from the cam-engager home position to the actuated position and rotation of the cam in the other direction causes the link to move from the first position to the second position to cause the weld arm to move from the weld-arm home position to the sealing position.

Description

STRAPPING DEVICEPriority

[0001] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 587,556, filed October 3, 2023, 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 to form a tensioned strap loop around the load.Background

[0003] Strapping tools 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. Many strapping tools utilize friction welding to attach overlapping upper and lower strap layers to one another. 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 and presses a button to initiate a tensioning process during which a tension 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 process, a sealing process is initiated. During the sealing process, a toothed weld shoe forces the strap layers against a toothed weld plate. A motor oscillates the weld shoe at a high frequency as the weld shoe exerts a welding force on the strap layers. The oscillating weld shoe oscillates 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 oscillating the weld shoe while the weld shoe continues to exert the welding force. The meltedportions of the overlapping strap layers join together and solidify as they cool, thereby attaching the upper and lower strap layers to form the tensioned strap loop.SummaryVarious embodiments of the present disclosure provide a strapping device including a support; a weld plate supported by the support; a motor; a weld arm comprising a weld pad, the weld arm movable between a weld-arm home position and a sealing position, wherein the weld pad is closer to the weld plate when the weld arm is in the sealing position than when the weld arm is in the weld-arm home position; a link movable from a first position to a second position to cause the weld arm to move from the weld-arm home position to the sealing position; a cam engager supported by the link and movable relative to the link between a cam-engager home position and an actuated position; and a rotatable cam positioned such that, when the weld arm is in the weld-arm home position, the link is in the first position, and the cam engager is in the camengager home position: rotation of the cam in a first rotational direction causes the link to move from the first position to the second position to cause the weld arm to move from the weld-arm home position to the sealing position; and rotation of the cam in a second rotational direction opposite the first rotational direction causes the cam engager to move from the cam-engager home position toward the actuated position to enable continued rotation of the cam in the second rotational direction.Brief Description of the Figures

[0004] Figures 1A and IB are perspective views of one example embodiment of a strapping device of the present disclosure.

[0005] Figure 1C is a block diagram of certain components of the strapping device of Figures 1A and IB.

[0006] Figures 2A-2C are diagrammatic views of the strapping device of Figures 1A and IB securing a load to a pallet.

[0007] Figure 2D is a perspective view of a friction- weld strap joint formed by the strapping device of Figures 1A and IB.

[0008] Figures 3A and 3B are perspective views of the working assembly of the strapping device of Figures 1A and IB.

[0009] Figure 4A is a side view of part of one side of the working assembly of Figures 3A and 3B showing the tensioning assembly in the home position. Certain components of the working assembly are not shown for clarity.

[0010] Figure 4B is similar to Figure 4A but shows the tensioning assembly in a strap-insertion position after strap has been inserted into the strapping device.

[0011] Figure 4C is similar to Figures 4A and 4B but shows the tensioning assembly in the tensioning position.

[0012] Figure 5 is a perspective view of the sealing assembly of the working assembly of Figures 3A and 3B.

[0013] Figure 6 is an exploded perspective view of the first link and the movable cam engager of the sealing assembly of Figure 5.

[0014] Figure 7A is a front elevational view corresponding to Figure 5 showing the sealing assembly in a home configuration.

[0015] Figure 7B is a front elevational view similar to Figure 7A but after the cam of the transmission gearing has moved in a first rotational direction and engaged the cam engager of the sealing assembly.

[0016] Figure 7C is a front elevational view similar to Figure 7B but after the cam of the transmission gearing has continued to move in the first rotational direction and forced the first link to pivot and move the sealing assembly from the home configuration to the sealing configuration.

[0017] Figure 7D is a front elevational view similar to Figure 7C but after the cam of the transmission gearing has been manually moved in a second rotational direction out of engagement with the cam engager of the sealing assembly.

[0018] Figure 7E is a front elevational view similar to Figure 7D but after continued manual movement of the cam of the transmission gearing in the second rotational direction.

[0019] Figure 7F is a front elevational view similar to Figure 7E but after continued manual movement of the cam of the transmission gearing in the second rotational direction has resulted in the cam engaging the cam engager of the sealing assembly and moving the cam engager toward its actuated position.Detailed Description

[0020] 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 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.

[0021] Figures 1A-7F show one example embodiment of a strapping device of the present disclosure in the form of a battery-powered portable strapping device 50 and certain assemblies and components thereof. As shown in Figures 2A-2C, the strapping device 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 2A. The operator then introduces the overlapped upper and lower layers UL and LL of the strap S into the strapping device 50 and actuates one or more buttons to initiate the strapping process. As shown in Figure 2B, a motor drives a tensioning assembly to carry out a tensioning process during which the strapping device 50 tensions strap S around the load L. Once a preset tension is reached in the strap S, as shown in Figure 2C, the motor drives a sealing assembly to carry out a sealing process during which the strapping device 50 connectsthe 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 2D, and cuts the strap S from the strap supply.

[0022] The strapping device 50 includes a housing 100, a working assembly 200, a cover 1300, first and second pushbutton actuators 1410 and 1440, a display assembly 1490, a power supply 1500, a controller 1600, and one or more sensors 1700.

[0023] The housing 100, which is shown in Figures 1A and IB, 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 device 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. The rear housing section 120 at least partially encloses and / or supports at least some of the components of the display assembly 1490 and defines a receptacle sized, shaped, and otherwise configured to receive and at least partially enclose and / or support the power supply 1500 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, including the motor 1100. 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 sized and shaped to be held by a hand of the operator. This is merely one example, and in other embodiments the components of the strapping device 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 cover 1300 is attached to the front housing section 110 and covers part of the working assembly 200.

[0024] The working assembly 200, which is best shown in Figures 3A and 3B, includes the majority of the components of the strapping device 50 that are configured to carry out the opening process to prepare the strapping device 50 to receive strap and to carry out the strapping process to tension the strap around the load, attach the overlapping layers of the strap to one another, and cut the strap from the strap supply. The working assembly 200 includes asupport 300, a tensioning assembly 400, a trigger 600, a sealing assembly 900, a transmission 1000, and a motor 1100.

[0025] The support 300 serves as a direct or indirect common mount for the tensioning assembly 400, the trigger 600, the sealing assembly 900, the transmission 1000, and the motor 1100. The support 300 includes a base 300b and a frame 300f extending from the base 300b. The base 300b supports a toothed tension plate 312 below the tension wheel 400w of the tensioning assembly 400 (described below) and a toothed weld plate 314 below the weld shoe 962 of the sealing assembly 900 (described below).

[0026] The tensioning assembly 400 is operable to tension the strap around the load during a tensioning process. The tensioning assembly 400 includes a rocker 400r, tensioningassembly gearing, and a tension wheel 400w. The tension wheel 400w is supported by and driven by the tensioning-assembly gearing, which is in turn supported by the rocker 400r. The tensioning assembly 400 is movably mounted to the support 300 via the rocker 400r and a tensioning-assembly mounting shaft 395 and configured to pivot relative to the support 300 — and particularly relative to the base 300b of the support 300 — about a rocker-pivot axis A4oor among a home position shown in Figure 4A, a strap-insertion position shown in Figure 4B, and a tensioning position shown in Figure 4C. When the tensioning assembly 400 is in the home position, the tension wheel 400w is adjacent to the tension plate 312 of the support 300. When the tensioning assembly 400 is in the strap-insertion position, the tension wheel 400w is spacedapart from the tension plate 312 to enable the overlapping upper and lower layers UL and LL of the strap S to be inserted between the tension wheel 400w and the tension plate 312. When the tensioning assembly 400 is in the tensioning position and the overlapping strap layers are between the tension wheel 400w and the tension plate 312, the tension wheel 400w engages the upper layer UL of the strap S and forces the strap layers onto the tension plate 312. The weight of the tensioning assembly 400 and one or more springs or other biasing elements (not shown) bias the tensioning assembly 400 to the home position.

[0027] The trigger 600 is actuatable to cause the tensioning assembly 400 to move from the home or tensioning position to the strap-insertion position. In this example embodiment, actuation of the trigger 600 causes the motor 1100 to activate to, via suitable components in the tensioning-assembly gearing, cause the tensioning assembly 400 to move from the home or tensioning position to the strap-insertion position. In other embodiments, thetrigger 600 is mechanically connected to the tensioning assembly 400, such as via one or more linkages, such that actuation of the trigger 600 raises the tensioning assembly 400 to the strapinsertion position.

[0028] The sealing assembly 900, which is best shown in Figures 3A and 5-7F, is configured to attach overlapping portions of the strap to one another to form a tensioned strap loop around the load during the sealing process via friction welding. The sealing assembly 900 includes a first link 910, a cam engager 920, a second link 940, a first sealing-assembly biasing element 950, a second sealing-assembly biasing element 952, a weld arm 960, a weld shoe 962, a cutter 964, a cam-engager biasing element 990, and an eccentric shaft (not shown).

[0029] As best shown in Figure 6, the first link 910 includes a body 912 and spacedapart, substantially parallel first and second arms 914 and 916 extending from one end of the body 912. First and second slots 914s and 916s are defined through the first and second arms 914 and 916 and are substantially aligned. The cam engager 920 includes a roller support 925 and a tubular roller 930. The roller support 925 includes a disc-shaped head 925a and a cylindrical shaft 925b extending from the head 925a. The roller 930 is positioned between the first and second arms 914 and 916 of the first link 910, and the shaft 925b of the roller support 925 extends through the first and second slots 914s and 916s and a central bore (not labeled) of the roller 930. A suitable retainer, such as a retaining clip, prevents the roller support 925 from sliding out of the slots and the roller. Since the first and second slots 914s and 916s are longer than the diameter of the shaft 925b of the roller support 925, the cam engager 920 is movable relative to the first link 910. Specifically, the cam engager 920 is movable between a home position — shown in Figures 7A-7E — when the shaft 925b is at one end of the first and second slots 914s and 916s and an actuated position — shown in Figure 7F — when the shaft 925b is at the opposite end of the first and second slots 914s and 916s. The cam-engager biasing element 990, which is a torsion spring in this example embodiment but may be any other suitable biasing element, biases the cam engager 920 to the home position.

[0030] The weld shoe 962 is slidably mounted to the weld arm 960 such that the weld shoe 962 can oscillate relative to the weld arm 960. The eccentric shaft is operably connected to the weld shoe 962 and configured to, when rotated, cause the weld shoe 962 to oscillate. A toothed belt 900b operably connects the transmission 1000 to the eccentric shaft to rotate the eccentric shaft. The cutter 964 is removably mounted to the weld arm 960. The weldarm 960 is pivotably mounted to the support 300 and is pivotable relative to the support 300 and the weld plate 314 about a weld-arm axis A960 between a home position (Figures 5, 7A, 7B, 7E, and 7F) in which the weld shoe 962 is spaced-apart from the weld plate 314 and a sealing position (Figures 7C and 7D) in which the weld shoe 962 is adjacent to the weld plate 314 and positioned to weld the strap.

[0031] The first link 910, the cam engager 920, and the second link 940 operably connect the transmission 1000 to the weld arm 960 such that the transmission 1000 can move the weld arm 960 from the home position to the sealing position. The first link 910 is pivotably mounted to the support 300 via a first pivot 900pl (such as a pivot pin) and movable — here, pivotable about the first pivot 900pl — between a first position (Figures 7A, 7B, 7E, and 7F) and a second position (Figures 7C and 7D). The second link 940 links the first link 910 to the weld arm 960. Specifically, one end of the second link 940 is pivotably connected to one end of the body 912 of the first link 910 via a second pivot 900p2 (such as a pivot pin), and the other end of the second link 940 is pivotably connected to the weld arm 960 via a third pivot 900p3 (such as a pivot pin). In this example embodiment, the first pivot 900pl is between the second pivot 900p2 and the slots 914s and 916s such that the first link 910 is pivotable about a first-link axis A910. The first sealing-assembly biasing element 950 circumscribes the second link 940.

[0032] When the sealing assembly 900 is in a home configuration in which the weld arm 960 is in the home position — shown in Figures 5, 7A, 7B, 7E, and 7F — the first and second links 910 and 940 are oriented such that they form an angle greater than 0 degrees and less than 180 degrees (i.e., an acute or obtuse angle). When the sealing assembly 900 is in a sealing configuration in which the weld arm 960 is in the sealing position — shown in Figures 7C and 7D — the first and second links 910 and 940 form an angle greater than 180 degrees and less than 360 degrees (i.e., a reflex angle). As described in detail below, the transmission 1000 is configured to switch the sealing assembly 900 from its home configuration to its sealing configuration by manipulating the first and second links 910 and 940 via moving the cam engager 920. The sealing-assembly biasing element 950 retains the sealing assembly 900 in the sealing configuration. The sealing assembly 900 switches back from its sealing configuration to its home position responsive to actuation of the trigger 600. Specifically, when actuated, the trigger 600 manipulates one or more release components to force the second pivot 900p2downward, which along with the various biasing elements causes the sealing assembly 900 to move back to its home configuration.

[0033] The transmission 1000, which is best shown in Figures 3A and 3B, is driven by the motor 1100, is operably connected to the tensioning assembly 400 and configured to cause the tension wheel 400w to rotate to tension the strap, and is operably connected to the sealing assembly 900 and configured to cause the sealing assembly 900 to attach the overlapping layers of the strap to one another. The transmission 1000 includes transmission gearing including suitable components (such as gears, bearing, and freewheels) that transmit rotational movement of the output shaft of the motor 1100 in a first drive direction to the tensioning-assembly gearing to rotate the to rotate the tension wheel 400w but not to drive any components of the sealing assembly 900 in this example embodiment. The components of the transmission gearing are also configured to transmit rotational movement of the output shaft of the motor 1100 in a second drive direction opposite the first drive direction to: (1) a ring gear 1010 including a cam 1010c to rotate the ring gear in a first rotational direction (counter-clockwise from the perspective shown in Figure 7A); and (2) the toothed belt 990 to rotate the eccentric and cause the weld shoe 962 to oscillate (but not to drive the tension wheel 400w in this example embodiment).

[0034] The cam 1010c is sized, shaped, oriented, positioned, and otherwise configured to engage the cam engager 920 of the sealing assembly 900 when the sealing assembly 900 is in the home configuration and when the cam engager 920 is in the home position. When the sealing assembly 900 is in the home configuration, rotation of the cam 1010c in the first rotational direction — counter-clockwise from the perspective shown in Figure 7A — this results in the sealing assembly moving to the sealing configuration. Conversely, rotation of the cam 1010c in a second rotational direction opposite the first rotational direction — clockwise from the perspective shown in Figure 7A — when the sealing assembly 900 is in the home configuration results in the cam 1010c forcing the cam engager 920 to move to the actuated position to enable the cam 1010c to continue rotating in the second rotational direction .

[0035] Figure 7A shows the sealing assembly 900 in the home configuration and the cam engager 920 in the home position. As the motor 1100 rotates the ring gear 1010, the cam 1010c moves in the first rotational direction (counter-clockwise) to contact the cam engager 920, and specifically the roller 930, as shown in Figure 7B. Since the cam engager 920 is at the bottom of — and thus cannot move within — the slots 914s and 916s, continued rotation of the ringgear 1010 and the cam 1010c in the first rotational direction causes the cam 1010c to force the first link 910 to pivot about the first pivot 91 Op 1 from the first position to the second position, thereby causing the second link 940 to pivot to force the weld arm 960 to the sealing position to complete movement of the sealing assembly 900 to the sealing configuration, as shown in Figure 7C.

[0036] The motor 1100 may deactivate while the cam 1010c is in a position in which the cam 1010c engages or is adjacent to the cam engager 920and prevents the first link 910 from pivoting back to the first position. This blocks the sealing assembly 900 from returning to the home configuration. To remedy this, the operator can manually rotate the ring gear 1010, such as via a screwdriver or other tool, in the second rotational direction (clockwise) to move the cam 1010c out of engagement with the cam engager 920. As the operator rotates the ring gear 1010 in the second rotational direction, the cam 1010c eventually moves out of engagement with or otherwise away from the cam engager 920, as shown in Figure 7D. At this point, the first link 910 is again free to pivot, and the sealing assembly 900 can be moved back to the home configuration, as shown in Figure 7E. At this point, the operator can stop rotating the ring gear 1010. But if the operator continues rotating the ring gear 1010, the cam 1010c will eventually reengage the cam engager 920 from the opposite side. As shown in Figure 7F, the cam engager 920 is positioned such that continued rotation of the ring gear 1010 and the cam 1010c in the second rotational direction results in the cam 1010c forcing the cam engager 920 to move to the actuated position and then — after the cam 1010c disengages the cam engager 920 — allow the cam engager 920 to move back to the home position. In other words, the ring gear 1010 can continuously rotate in the second rotational direction in this configuration.

[0037] This ability of the ring gear to continuously rotate in the second rotational direction when the sealing assembly is in the home configuration improves upon certain prior art strapping devices. Specifically, certain prior art strapping devices include a cam engager that is fixedly attached to the first link. In these strapping devices, if the operator rotates the ring gear back into engagement with the cam engager after the sealing assembly moves to the home configuration, the cam engager will prevent continued rotation of the ring gear. If the operator does not recognize this and continues to try to rotate the ring gear, the transmission could become damaged, requiring costly repairs. Since the cam engager of the present disclosure ismovable, it enables the ring gear to continuously rotate and eliminates the possibility that manual rotation of the ring gear will damage the transmission.

[0038] The motor 1100, which is best shown in Figures 3 A and 3B, is operably connected to (via the transmission 1000) the tensioning assembly 400 and the sealing assembly 900 and is configured to drive those assemblies as explained herein. The motor 1100 includes the output shaft (not shown) referenced above. The motor 1100 is an electric motor in this example embodiment but may be any suitable motor.

[0039] The display assembly 1490, which is shown in Figures 1A-1C, includes a suitable display screen 1492 with a touch panel 1494. The display screen 1492 is configured to display information regarding the strapping device 50 (at least in this embodiment), and the touch screen 1494 is configured to receive operator inputs such as a desired strap tension and desired weld cooling time. A display controller (not shown) may control the display screen 1492 and the touch panel 1494 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 device do not include a touch panel. Still other embodiments of the strapping device do not include a display assembly. Certain embodiments of the strapping device include a separate pushbutton panel instead of a touch panel beneath or integrated with the display screen.

[0040] The first and second pushbutton actuators 1410 and 1440 are operable to initiate the tensioning and / or sealing processes as described below. Other embodiments of the strapping device 50 do not have pushbutton actuators and instead incorporate their functionality into the display assembly 1490. 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.

[0041] The controller 1600, which is shown in Figure 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 specialpurpose processor, a digital -signal processor, one or more microprocessors, one or more microprocessors in association with a digital-signal 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 memorydevice 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 device 50. The controller 1600 is communicatively and operably connected to the motor 1100, the display assembly 1490, the pushbutton actuators 1410 and 1440, 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.

[0042] The controller 1600 is configured to operate the strapping device in one of three operating modes to carry out the strapping process: (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 1100 to cause the tension wheel 400w to rotate responsive to the first pushbutton actuator 1410 being actuated and maintained in its actuated state. The controller 1600 operates the motor 1100 to cause the sealing assembly 900 to carry out the sealing process responsive to the second pushbutton actuator 1440 being actuated. In the semi-automatic operating mode, the controller 1600 operates the motor 1100 to cause the tension wheel 400w 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 1100 to cause the sealing assembly 900 to carry out the sealing process (without requiring additional input from the operator). In the automatic operating mode, the controller 1600 operates the motor 1100 to cause the tension wheel 400w 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 1100 to cause the sealing assembly 900 to carry out the sealing process (without requiring additional input from the operator).

[0043] The sensors 1700 include any suitable sensors, such as microswitches, optical sensors, ultrasonic sensors, magnetic position sensors, and the like, configured to detect theposition of certain components of the strapping device 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 400 is in its home position and / or its strap-insertion position; one or more trigger-position sensors configured to detect when the trigger 600 is pulled; and one or more actuating assembly sensors configured to detect actuation of the first and second pushbutton actuators 1410 and 1440.

[0044] The power supply 1500 is electrically connected to (via suitable wiring and other components) and configured to power several components of the strapping device 50, including the motor 1100, the display assembly 1490, the controller 1600, and the sensor(s) 1700. The power supply 1500 includes a rechargeable battery (such as a lithium-ion or nickel cadmium battery) in this example embodiment, though it may be any other suitable electric power supply in other embodiments. The power supply 1500 is sized, shaped, and otherwise configured to be received in the receptacle defined by the rear housing section 120 of the housing 100. The strapping device 50 includes one or more power-supply-securing devices (not shown) to releasably lock the power supply 1500 in place upon receipt in the receptacle. Actuation of a release device of the strapping device 50 or the power supply 1500 unlocks the power supply 1500 from the housing 100 and enables an operator to remove the power supply 1500 from the receptacle.

[0045] One example use of the strapping device 50 to form a tensioned strap loop around a load is described below. Initially, the tensioning assembly 400 is in its home position and the sealing assembly 900 is in its home configuration. The strapping device 50 is in the automatic mode for the purposes of this example.

[0046] 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 layer of the strap to form upper and lower layers of strap. The operator then pulls the trigger 600 to cause the tensioning assembly 400 to pivot upward about the rocker axis A4oor to its strapinsertion position. With the tensioning assembly 400 in its strap-insertion position and while continuing to pull the trigger 600, the operator introduces the overlapping upper and lower layers UL and LL of the strap S between the tension wheel 400w and the tension plate 312 and between the weld shoe 962 and the weld plate 314. The operator then releases the trigger 600, enablingthe appropriate biasing elements to force the tensioning assembly 400 to move to its tensioning position.

[0047] The operator then actuates the first pushbutton actuator 1410. Once one of the sensors 1700 detects the actuation of the first pushbutton actuator 1410, the controller 1600 initiates the strapping process by first carrying out a tensioning process. The controller 1600 controls the motor 1100 to rotate the output shaft in the first drive direction. As explained above, the transmission 1000 transmits this rotational movement of the output shaft to the tensioningassembly gearing of the tensioning assembly 400 to rotate the tension wheel 400w about the tension-wheel rotational axis A4oo . As the tension wheel 400w rotates in the tensioning direction T, it pulls the upper layer UL of the strap S over the lower layer LL of the strap S, thereby tensioning the strap S around the load. Throughout the tensioning process, the controller 1600 monitors the electrical current drawn by the motor 1100. When this current reaches a preset value that is correlated with the (preset) desired strap tension for this strapping process, the controller 1600 stops the motor 1100, thereby terminating the tensioning process.

[0048] After completion of the tensioning process, the controller 1600 automatically starts the sealing process by controlling the motor 1100 to begin rotating the output shaft in the second drive direction. This causes the transmission 1000 to drive the toothed belt 900b to begin rotating the eccentric and oscillating the weld shoe 962 and begin rotating the ring gear 1010 and the cam 1010c thereon in the first rotational direction. As explained above, the cam 1010c eventually engages the cam engager 920, forces the cam engager 920 to move to the actuated position, and then forces the first link 910 to pivot to move the sealing assembly 900 into its sealing configuration. As the weld arm 960 reaches the welding position, the weld shoe 962 forces the overlapping upper and lower layers of strap against the weld plate 314 while the cutter 964 cuts the upper strap layer from the strap supply. The oscillating movement of the weld shoe 962 locally melts the portions of the upper and lower strap layers together. After a preset period of time or a preset quantity of rotations of the motor output shaft, the controller 1600 controls the motor 1100 to stop rotating the output shaft, completing the sealing process.

[0049] The above-described example embodiments of the strapping device includes a single motor configured to drive both the tensioning assembly and the sealing assembly. In other embodiments, the strapping device includes separate motors configured to drive therespective tensioning and sealing assemblies and may include separate transmissions for each motor.

[0050] Other embodiments of the strapping device may include fewer assemblies, components, and / or features than those included in the strapping device 50 described above and shown in the Figures. In other words, while the strapping device 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 devices.

[0051] While the strapping device described above is a handheld strapping device, the strapping device may be any other suitable strapping device in other embodiments, such as a standalone automatic or semi-automatic strapping machine.

Claims

Claims1. A strapping device comprising: a support; a weld plate supported by the support; a motor; a weld arm comprising a weld pad, the weld arm movable between a weld-arm home position and a sealing position, wherein the weld pad is closer to the weld plate when the weld arm is in the sealing position than when the weld arm is in the weld-arm home position; a link movable from a first position to a second position to cause the weld arm to move from the weld-arm home position to the sealing position; a cam engager supported by the link and movable relative to the link between a camengager home position and an actuated position; and a rotatable cam positioned such that, when the weld arm is in the weld-arm home position, the link is in the first position, and the cam engager is in the cam-engager home position: rotation of the cam in a first rotational direction causes the link to move from the first position to the second position to cause the weld arm to move from the weld-arm home position to the sealing position; and rotation of the cam in a second rotational direction opposite the first rotational direction causes the cam engager to move from the cam-engager home position toward the actuated position to enable continued rotation of the cam in the second rotational direction.

2. The strapping device of claim 1, further comprising a second link operably connecting the first link to the weld arm such that movement of the link from the first position to the second position causes the second link to move to force the weld arm to move from the weldarm home position to the sealing position.

3. The strapping device of claim 1, wherein the link is pivotable between the first position and the second position and the weld arm is pivotable between the weld-arm home position and the sealing position.

4. The strapping device of claim 1, wherein the cam engager comprises a rotatable roller.

5. The strapping device of claim 4, wherein the link comprises a body, a first arm extending from the body, and a second arm extending from the body, wherein the roller is positioned between the first and second arms of the link.

6. The strapping device of claim 5, wherein the cam engager further comprises a roller support supporting the roller, wherein first and second slots are defined through the first and second arms, respectively, of the link, and wherein the roller support extends through at least one of the first and second slots such that the at least one of the first and second slots constrains movement of the cam engager between the cam-engager home position and the actuated position.

7. The strapping device of claim 6, wherein the roller support comprises a shaft, wherein the shaft is positioned at one end of the at least one of the first and second slots when the cam engager is in the cam-engager home position and at an opposite end of the at least one of the first and second slots when the cam engager is in the actuated position.

8. The strapping device of claim 1, further comprising a cam-engager biasing element biasing the cam engager to the cam-engager home position.

9. The strapping device of claim 8, wherein the cam is positioned to engage the cam engager to move the cam engager from the cam-engager home position to the actuated position.

10. The strapping device of claim 9, wherein the cam is positioned such that continued rotation of the cam in the second rotational direction after the cam engager engages the cam causes the cam to disengage the cam engager to enable the cam-engager biasing element to force the cam engager to return to the cam-engager home position.

11. The strapping device of claim 10, wherein the cam is positioned such that continued rotation of the cam after the cam disengages the cam-engager and the cam engager returns to the cam-engager home position causes the cam to again engage the cam engager andmove the cam engager from the cam-engager home position to the actuated position without causing the first link to move.

12. The strapping device of claim 11, wherein the cam engager comprises a rotatable roller engageable by the cam.

13. The strapping device of claim 12, wherein the link comprises a body, a first arm extending from the body, and a second arm extending from the body, wherein the roller is positioned between the first and second arms of the link.

14. The strapping device of claim 13, wherein the cam engager further comprises a roller support supporting the roller, wherein first and second slots are defined through the first and second arms, respectively, of the link, and wherein the roller support extends through at least one of the first and second slots such that the at least one of the first and second slots constrains movement of the cam engager between the cam-engager home position and the actuated position.

15. The strapping device of claim 14, wherein the roller support comprises a shaft, wherein the shaft is positioned at one end of the at least one of the first and second slots when the cam engager is in the cam-engager home position and at an opposite end of the at least one of the first and second slots when the cam engager is in the actuated position.

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