Strapping device with a combined tensioning-and-welding assembly

Abstract

Various embodiments of the present disclosure provide a strapping device including a tensioning-and-welding plate, a tensioning-and-welding wheel, a rotatable welding actuator, and at least one motor. The tensioning-and-welding wheel is rotatable relative to the tensioning-and-welding plate and axially movable relative to the tensioning-and-welding plate between a first axial position and a second axial position. The welding actuator is operably connected to the tensioning-and-welding wheel such that rotation of the welding actuator forces the tensioning-and-welding wheel to axially move in a reciprocating manner between the first and second axial positions. The at least one motor is operably connected to the tensioning-and-welding wheel to rotate the tensioning-and-welding wheel and to the welding actuator to rotate the welding actuator.

Description

STRAPPING DEVICE WITH A COMBINED TENSIONING- AND-WELDING ASSEMBLYPriority

[0001] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 589,097, filed October 10, 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 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 process 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 process, a sealing process is initiated. During the sealing process, 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 together 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 including a tensioning-and-welding plate, a tensioning-and-welding wheel, a rotatable welding actuator, and at least one motor. The tensioning-and-welding wheel is rotatable relative to the tensioning-and-welding plate and axially movable relative to the tensioning-and-welding platebetween a first axial position and a second axial position. The welding actuator is operably connected to the tensioning-and-welding wheel such that rotation of the welding actuator forces the tensioning-and-welding wheel to axially move in a reciprocating manner between the first and second axial positions. The at least one motor is operably connected to the tensioning-and- welding wheel to rotate the tensioning-and-welding wheel and to the welding actuator to rotate the welding actuator.Brief Description of the Figures

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

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

[0011] Figures 2A-2C are diagrammatic views of the strapping tool of Figure 1 A securing a load to a pallet.

[0012] Figure 2D is a perspective view of a friction-weld strap joint formed by the strapping device of Figures 1A and IB.

[0013] Figures 3 A and 3B are perspective views of the working assembly of the strapping tool of Figure 1 A.

[0014] Figures 4A and 4B are similar to Figures 3A and 3B but with certain components of the working assembly removed.

[0015] Figure 5A is a perspective view of the tensioning-and-welding assembly of the working assembly of Figures 3 A and 3B.

[0016] Figure 5B is an exploded perspective view of the tensioning-and-welding assembly of Figure 5 A.

[0017] Figure 5C is a cross-sectional perspective view of the tensioning-and-welding assembly of Figure 5 A taken along line 5C-5C of Figure 5 A.

[0018] Figure 6 is a front elevational view of the first retainer of the tensioning-and- welding assembly of Figures 5A-5C.

[0019] Figure 7 is a front elevational view of the second retainer of the tensioning- and-welding assembly of Figures 5A-5C.

[0020] Figures 8A and 8B are perspective views of the welding actuator of the tensioning-and-welding assembly of Figures 5A-5C.

[0021] Figure 8C is a side elevational view of the welding actuator of Figures 8 A and 8B.

[0022] Figure 8D is a front elevational view of the welding actuator of Figures 8A and 8B.

[0023] Figures 9A-9E are side elevational views of the tensioning-and-welding assembly of Figures 5A-5C and the tensioning-and-welding plate of the support of the working assembly of Figures 3 A and 3B as the welding actuator rotates and the tensioning-and-welding wheel moves axially relative to the tensioning-and-welding plate.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 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.

[0025] Figures 1A-9E 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 assemblies and components thereof. As shown in Figures 2A-2C, the strapping tool 50 is configured to carry out a strapping process to tension and seal strap S (plastic strap in thisexample 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 tool 50 and actuates one or more buttons to initiate the strapping process. As shown in Figure 2B, the strapping tool 50 first carries out a tensioning process 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 2C, the strapping tool 50 carries out a sealing process 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 2D, and cuts the strap S from the strap supply.

[0026] The strapping tool 50 includes a housing 100, a working assembly 200, a display assembly 1300, an actuating assembly 1400, a power supply, a controller 1600, and one or more sensors 1700.

[0027] The housing 100, which is shown in Figure 1A, is formed from multiple components that collectively at least partially enclose and / or support some or all of the other assemblies and components of the strapping tool 50. In this example embodiment, the housing 100 includes a front housing section 110, a rear housing section 120, and a handle section 150. The front housing section 110 at least partially encloses and / or supports at least some of the components of the working assembly 200 and the actuating assembly 1400. The rear housing section 120 at least partially encloses and / or supports at least some of the components of the display assembly 1300 and defines a receptacle 122 sized, shaped, and otherwise configured to receive and at least partially enclose and / or support the power supply and the controller 1600. The handle housing section 150 extends between and connects the tops bottoms of the front and rear housing sections 110 and 120 and defines a handle usable by the operator. This is merely one example, and in other embodiments the components of the strapping tool may be supported and / or enclosed by any suitable portion of the housing 100. The housing 100 may take any suitable shape and 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 200, which is best shown in Figures 1 A and 3 A-4B, includes the majority 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 200 includes a support 300, a tensioning-and- welding assembly 400, a transmission 500, a motor 600, and a hand lever 800.

[0029] The support 300, which is best shown in Figures 3A-4B, serves as a direct or indirect common mount for the tensioning-and-welding assembly 400, the transmission 500, and the motor 600. The support 300 includes a base 310, a first mount 320a, a second mount 320b, a third mount 320c, a fourth mount 320d, a fifth mount 320e, and a tensioning-and-welding plate 330. The base 310 is generally rectangular, and the first, second, third, fourth, and fifth mounts 320a, 320b, 320c, 320d, and 320e extend upward from and in this embodiment are integrally formed with the base 310. The mounts 320 serve as mounts for various components of the working assembly 200 as described below. The tensioning-and-welding plate 330 includes a concave, toothed tensioning-and-welding surface. This is merely one example configuration of the support 300, and other embodiments may be configured differently.

[0030] The tensioning-and-welding assembly 400, which is best shown in Figures 5A-8D, is configured to tension the strap around the load during the tensioning process and locally melt overlapping portions of the strap and join them together to form a tensioned strap loop around the load during the sealing process via friction welding. The tensioning-and-welding assembly 400 includes a driven shaft 405; first and second collars 410a and 410b; first and second spacer seats 412a and 412b; a tensioning-and-welding wheel 415; tensioning-and- welding-wheel fasteners 415f; a welding-actuator housing 420; a first retainer 425; first-retainer fasteners 425f; first-retainer locating pins 425p; a second retainer 430; second-retainer fasteners 430f; second-retainer locating pins 430p; first spacers 435; second spacers 445; a welding actuator 450; and a bearing 450b.

[0031] The driven shaft 405 is sized, shaped, positioned, oriented, and otherwise configured to be drivingly engaged by the transmission 500, as described below, and to rotate about an axis A415, which in this example embodiment is coaxial with a longitudinal axis of the driven shaft 405. In this example embodiment, the driven shaft 405 is a splined shaft.

[0032] The first and second collars 410a and 410b are fixedly mounted to the driven shaft 405 in a spaced-apart manner and such that the first and second collars 410a and 410b arerotatable with the driven shaft 405 about the axis A415 and are axially movable with the driven shaft 405 along the axis A415. In this example embodiment, the first and second collars 410a and 410b include splined clamp collars, though they may be any suitable components in other embodiments.

[0033] The tensioning-and-welding wheel 415 includes an annular body that is substantially enclosed on one side by a mounting plate and that has a toothed outer cylindrical surface. The tensioning-and-welding-wheel fasteners 415f attach the tensioning-and-welding wheel 415 to the first collar 410a via the mounting plate of the tensioning-and-welding wheel 415. Once attached, the tensioning-and-welding wheel 415 is rotatable with the first collar 410a and the driven shaft 405 about the axis A415 and is axially movable with the first collar 410a and the driven shaft 405 along the axis A415.

[0034] The welding-actuator housing 420 is substantially tubular and serves as a mount for the first and second retainers 425 and 430 and the welding actuator 450. The weldingactuator housing 420 circumscribes — but does not contact — the driven shaft 405 and is positioned between the first and second collars 410a and 410b.

[0035] The first retainer 425, best shown in Figure 6, enables the first spacers 425 to axially move in a direction parallel to the axis A415 while preventing them from rotating about the axis A415 or falling out of the tensioning-and-welding assembly 400. The first retainer 425 includes an annular hub 425h and multiple circumferentially spaced arms 425a extending radially outward from the hub 425h. In this example embodiment, the arms 425a are substantially equally circumferentially spaced, though the spacing may differ in other embodiments. The hub 425h defines five cylindrical spacer-receiving bores 425o therethrough. The spacer-receiving bores 425o are each sized and shaped to receive one of the first spacers 435, as described below. In this example embodiment, the center of each spacer-receiving bore 425o is positioned at a radius R from the center of the hub 425h, which is positioned on the axis A415. Additionally, in this example embodiment, the spacer-receiving bores 425o are equally circumferentially spaced such that the center of each spacer-receiving bore 425o is angularly offset from the center of each adjacent spacer-receiving bore 425o by an angle a, which is 72 degrees in this example embodiment. This spacing may differ in other embodiments.

[0036] The first retainer 425 is fixedly attached to the end of the welding-actuator housing 420 adjacent the first collar 410a via the first-retainer fasteners 425f and the first-retainer locating pins 425p extending through suitable bores through the arms 425a and into the welding-actuator housing 420. The first spacer seat 412a — which is an annular washer in this example embodiment but may be any suitable component — circumscribes the driven shaft 405 and is positioned between and separates the first collar 410a and the first spacers 435.

[0037] The second retainer 430, best shown in Figure 7, serves to enable the second spacers 445 to move in a direction parallel to the axis A415 while preventing them from rotating about the axis A415 or falling out of the tensioning-and-welding assembly 400. The second retainer 430 includes an annular hub 43 Oh and multiple circumferentially spaced arms 430a extending radially outward from the hub 430h. In this example embodiment, the arms 430a are substantially equally circumferentially spaced, though the spacing may differ in other embodiments. The hub 430h defines five cylindrical spacer-receiving bores 430o therethrough. The spacer-receiving bores 43 Oo are each sized and shaped to receive one of the second spacers 445, as described below. In this example embodiment, the center of each spacer-receiving bore 430o is positioned at a radius R from the center of the hub 430h, which is positioned on the axis A415. Additionally, in this example embodiment, the spacer-receiving bores 430o are equally circumferentially spaced such that the center of each spacer-receiving bore 430o is angularly offset from the center of each adjacent spacer-receiving bore 43 Oo by the angle a. This spacing may differ in other embodiments.

[0038] The second retainer 430 is fixedly attached to the end of the welding-actuator housing 420 adjacent the second collar 410b via the second-retainer fasteners 43 Of and the second-retainer locating pins 43 Op extending through suitable bores through the arms 430a and into the welding-actuator housing 420. The second spacer seat 412b — which is an annular washer in this example embodiment but may be any suitable component — circumscribes the driven shaft 405 and is positioned between and separates the second collar 410b and the second spacers 445.

[0039] The welding actuator 450, which is best shown in Figures 8A-8D, is actuatable by the transmission 500 to cause the tensioning-and-welding wheel 415 to axially move along the axis A415 relative to the tensioning-and-welding plate 330. The welding actuator 450 includes an annular driven portion 452, an annular first actuating portion 454 connected to (and in this example embodiment integrally formed with) and coaxial with the driven portion 452, and an annular second actuating portion 456 connected to (and in this example embodimentintegrally formed with) and coaxial with the driven portion 452. The driven portion 452 includes teeth 452t that extend around its outer surface and that are sized, shaped, positioned, oriented, and otherwise configured to be drivingly engaged by the transmission 500, as described below.

[0040] The first actuating portion 454 includes an annular first actuating surface 454s. As shown in Figure 8D, the first actuating surface 454s is centered at the radius R from the center of the first actuating portion 454, which corresponds to the axis A415 when the welding actuator 450 is mounted to the welding-actuator housing 420, as described below. As best shown in Figures 8A and 8C, the first actuating surface 454s has an undulating profile that defines alternating peaks 454p and valleys 454v (five of each, though any suitable quantity may be employed). The first actuating surface 454s is furthest from the driven portion 452 at the peaks 454p and closest to the driven portion 452 at the valleys 454v. As shown in Figure 8D, the peaks 454p are equally circumferentially spaced so each peak 454p is angularly offset from each adjacent peak 454p by the angle a, and the valleys 454v are equally circumferentially spaced so each valley 454v is angularly offset from each adjacent valley 454v by the angle a.

[0041] The second actuating portion 456 is identical to — but angularly offset from — the first actuating portion 454. The second actuating portion 456 includes an annular second actuating surface 456s. The second actuating surface 456s is centered at the radius R from the center of the second actuating portion 456, which corresponds to the axis A415 when the welding actuator 450 is mounted to the welding-actuator housing 420, as described below. As best shown in Figures 8B and 8C, the second actuating surface 456s has an undulating profile that defines alternating peaks 456p and valleys 456v (five of each, though any suitable quantity may be employed). The second actuating surface 456s is furthest from the driven portion 452 at the peaks 456p and closest to the driven portion 452 at the valleys 456v. The peaks 456p are equally circumferentially spaced so each peak 456p is angularly offset from each adjacent peak 456p by the angle a, and the valleys 456v are equally circumferentially spaced so each valley 456v is angularly offset from each adjacent valley 456v by the angle a. As best shown in Figure 8C, the second actuating portion 456 is angularly offset from first actuating portion 454 by the angle a / 2 such that the peaks 454p of the first actuating portion 454 substantially align with the valleys 456v of the second actuating portion 456 and such that the valleys 454v of the first actuating portion 454 substantially align with the peaks 456p of the second actuating portion 456.

[0042] The welding actuator 450 is rotatably mounted to the welding-actuator housing 420 between the first and second retainers 425 and 430 via the bearing 450b. Specifically, in this example embodiment, the outer race of the bearing 450b is mounted to the welding-actuator housing 420 via interference fit, and the inner race of the bearing 450b is mounted to the welding actuator 450 via interference fit, though the welding actuator may be rotatably mounted to the welding-actuator housing in any suitable manner in other embodiments. The first actuating surface 454s faces in the direction of the first spacer seat 412a, and the second actuating surface 456s faces in the direction of the second spacer seat 412b.

[0043] Each first spacer 435 is received in a different one of the spacer-receiving bores 425o of the first retainer 425 and — due to the above-described shapes, sizes, positions, and orientations of various components of the tensioning-and-welding assembly 400 — is positioned between and contacts the first spacer seat 412a and the first actuating surface 454s of the first actuating portion 454 of the welding actuator 450. While this embodiment includes five first spacers, other embodiments may have any suitable quantity of one or more first spacers. Similarly, each second spacer 445 is received in a different one of the spacer-receiving bores 430o of the second retainer 430 and — due to the above-described shapes, sizes, positions, and orientations of various components of the tensioning-and-welding assembly 400 — is positioned between and contacts the second spacer seat 412b and the second actuating surface 456s of the second actuating portion 454 of the welding actuator 450. While this embodiment includes five second spacers, other embodiments may have any suitable quantity of one or more second spacers.

[0044] Due to the undulating shapes of the first and second actuating surfaces 454s and 456s and the ability of the tensioning-and-welding wheel 415 — along with the driven shaft 405, the first and second collars 410a and 410b, and the first and second spacer seats 412a and 412b — to move axially along the axis A415, the rotational position of the welding actuator 450 controls the longitudinal position of the tensioning-and-welding wheel 415. When the welding actuator 450 is in a first rotational position, shown in Figure 9A, the first spacers 435 engage the valleys 454v of the first actuating surface 454s, and the second spacers 445 engage the peaks 456p of the second actuating surface 456s. When the welding actuator 450 is in the first rotational position, the tensioning-and-welding wheel 415 is in a first axial position relative tothe tensioning-and-welding plate 330. In this example embodiment, the tensioning-and-welding wheel 415 is as close as it can get to the welding actuator 450 when in the first axial position.

[0045] As the welding actuator 450 begins to rotate about the axis A415 under control of the transmission 500 (as described below): (1) the portions of the first actuating surface 454s engaging the first spacers 435 begin transitioning from the valleys 454v toward the peaks 454p; and (2) the portions of the second actuating surface 456s engaging the second spacers 445 begin transitioning from the peaks 456p toward the valleys 456v, as shown in Figure 9B. These transitions result in the first actuating surface 454s exerting a force on each of the first spacers 435 along a vector directed toward the first spacer seat 412a and aligned substantially parallel to the axis A415. Since the welding actuator 450 cannot move axially along the axis A415, this force causes the first spacer seat 412a to move against the first collar 410a and the first collar 410a, the first spacer seat 412a, and the tensioning-and-welding wheel 415 connected to the collar 410a to move axially away from the welding actuator 450 along the axis A415 and relative to the tensioning-and-welding plate 330. And since the first and second collars 410a and 410b are fixed to the driven shaft 405, this movement also results in the driven shaft 405, the second collar 410b, and the second spacer seat 412b to move along with the first collar 410a and the first collar 410a, the first spacer seat 412a, and the tensioning-and-welding wheel 415.

[0046] Eventually, and after rotating the angle a / 2 from the first rotational position in this example embodiment, the welding actuator 450 reaches a second rotational position at which the first spacers 435 engage the peaks 454p of the first actuating surface 454s and the second spacers 445 engage the valleys 456v of the second actuating surface 456s, as shown in Figure 9C. When the welding actuator 450 is in the second rotational position, the tensioning- and-welding wheel 415 is in a second axial position relative to the tensioning-and-welding plate 330. In this example embodiment, the tensioning-and-welding wheel 450 is as far as it can get from the welding actuator 450 when in the second axial position.

[0047] As the welding actuator 450 continues rotating: (1) the portions of the first actuating surface 454s engaging the first spacers 435 begin transitioning from the peaks 454p toward the valleys 454v; and (2) the portions of the second actuating surface 456s engaging the second spacers 445 begin transitioning from the valleys 456b toward the peaks 456p, as shown in Figure 9D. These transitions result in the second actuating surface 456s exerting a force on each of the second spacers 445 along a vector directed tow ard the second spacer seat 412b and alignedsubstantially parallel to the axis A415. Since the welding actuator 450 cannot move axially along the axis A415, this force causes the second spacer seat 412b to move against the second collar 410b and the second collar 410b and the second spacer seat 412b to move axially away from the welding actuator 450 along the axis A415 and relative to the tensioning-and-welding plate 330. Since the first and second collars 410a and 410b are fixed to the driven shaft 405, this movement also results in the driven shaft 405, the first collar 410a, the first spacer seat 412a, and the tensioning-and-welding wheel 415 to move along with the second collar 410a and the second spacer seat 412b. Specifically, the tensioning-and-welding wheel 415 begins moving from the second axial position back toward the first axial position.

[0048] Eventually, and after rotating the angle a / 2 from the second rotational position in this example embodiment, the welding actuator 450 reaches the first rotational position at which the first spacers 435 engage the valleys 454v of the first actuating surface 454s, the second spacers 445 engage the peaks 456p of the second actuating surface 456s, and the tensioning-and-welding wheel is in the first axial position, as shown in Figure 9E.

[0049] The motor 600, which is best shown in Figures 3A-4B, is mounted to the fourth and fifth mounts 320d and 320e of the support 300 and includes a motor housing and a rotatable motor output shaft extending from the motor housing. As shown in Figure 4B, the motor 600 is configured to rotate the motor output shaft in opposing tensioning and sealing rotational directions TD and SD to carry out the tensioning and sealing processes, respectively, as explained below. The motor 600 includes an electric motor in this example embodiment but may include any suitable motor or other actuator in other embodiments.

[0050] The transmission 500, which is best shown in Figures 4A and 4B, is driven by the motor 600 and is operably connected to the tensioning-and-welding assembly 400 and configured to cause the tensioning-and-welding assembly 400: (1) tension the strap around the load during the tensioning process by rotating the tensioning-and-welding wheel 415 about the axis A415; and (2) locally melt the strap via friction welding during the sealing process by moving the tensioning-and-welding wheel 415 axially along the axis A415 in a reciprocating manner. To do so, the transmission 500 is configured to: (1) transmit output from the motor 600 to the driven shaft 405 when the motor 600 rotates the motor output shaft in the tensioning rotational direction RD; and (2) transmit output from the motor 600 to welding actuator 450 when the motor 600 rotates the motor output shaft in the sealing rotational direction SD. The transmission assembly500 includes a first transmission-gear assembly 510 and a second transmission-gear assembly 520.

[0051] The first transmission-gear assembly 510 operably connects the motor 600 to the driven shaft 405 of the tensioning-and-welding assembly 400 so the motor 600 can rotate the driven shaft 405 and, therefore, the tensioning-and-welding wheel 415 that rotates with the driven shaft 405 via its connection to the first collar 410a that is itself fixed in rotation with the driven shaft 405. Specifically, the first transmission-gear assembly 510 includes suitable gearing — such as one or more planetary gear reductions — and other components (such as one or more freewheels) that operably connect the motor output shaft of the motor 600 to the driven shaft 405 so the first transmission-gear assembly 510: (1) transmits rotational movement of the motor output shaft in the tensioning rotational direction to the driven shaft 405 to rotate the driven shaft 405 in the tensioning rotational direction; and (2) does not transmit rotational movement of the motor output shaft in the sealing rotational direction to the driven shaft 405. For instance, in this example embodiment, the first transmission-gear assembly 510 includes a splined hub 512 including a hub portion 512h and a shaft portion 512s integrally formed with one another. Part of the driven shaft 405 adjacent the second collar 410b is received in and drivingly engaged by the shaft portion 512s. In operation, the remaining components of the first transmission-gear assembly 510 cause the splined hub 512 to rotate, and the splined hub 512 transmits this rotational movement to the driven shaft 405. This is one example configuration of the first transmission-gear assembly 510, and the first transmission-gear assembly 510 may take any other suitable configuration in other embodiments.

[0052] The second transmission-gear assembly 520 operably connects the motor 600 to the welding actuator 450 of the tensioning-and-welding assembly 400 so the motor 600 can rotate the welding actuator 450 and move the tensioning-and-welding wheel 415 axially as described above. The second transmission-gear assembly 520 includes a drive gear 522, a drivegear freewheel, a driven shaft 524, a first driven gear 526, a second driven gear 528, a first connector 520b 1, and a second connector 520b2.

[0053] The drive-gear freewheel is mounted to, engages, and circumscribes the motor output shaft of the motor 600. The drive gear 522, which is a gear pulley in this example embodiment, is mounted to, engages, and circumscribes the drive-gear freewheel. The drive-gear freewheel is configured to: (1) transmit rotational movement of the motor output shaft in thesealing rotational direction to the drive gear 522 so the drive gear 522 and the motor output shaft rotate together in the welding rotational direction about the axis A415; and (2) not transmit rotational movement of the motor output shaft in the tensioning rotational direction to the to the drive gear 522 so the motor output shaft rotates about the axis A415 in the tensioning rotational direction relative the drive gear 522.

[0054] The driven shaft 524 is rotatably mounted to (such as via suitable bearings) and extends between the first, second, and third mounts 320a, 320b, and 320c of the support 300 so the driven shaft 524 can rotate relative to the support 300 about a driven-gear-shaft rotational axis A524. In this example embodiment, the driven-gear-shaft rotational axis A524 is parallel to the axis A415, though these axes may be transverse to one another in other embodiments. The first driven gear 526, which is a gear pulley in this example embodiment, is fixedly mounted to the driven shaft 524 near one end of the driven shaft 524 and the second driven gear 528, which is a gear pulley in this example embodiment, is fixedly mounted to the driven shaft 524 near the opposite end of the driven shaft 524 so the driven shaft 524 and the first and second driven gears 526 and 528 rotate together about the driven-gear- shaft rotational axis A524.

[0055] The first connector 520bl, which is a toothed belt in this example embodiment but may be any suitable connector, operably connects the drive gear 522 and the first driven gear 524. The second connector 520b2, which is a toothed belt in this example embodiment but may be any suitable connector, operably connects the second driven gear 528 and the driven portion 452 of the welding actuator 450.

[0056] When the motor 600 rotates the motor output shaft in the tensioning rotational direction TD, the first transmission-gear assembly 510 transmits this rotational movement to the driven shaft 405 of the tensioning-and-welding assembly 400, which causes driven shaft 405 and the tensioning-and-welding wheel 415 to rotate in the tensioning rotational direction TD about the axis A415. The drive-gear freewheel does not transmit the rotational movement of the motor output shaft to the drive gear 522, which remains stationary.

[0057] Conversely, when the motor 600 rotates the motor output shaft in the sealing rotational direction SD, the drive-gear freewheel transmits this rotational movement to the drive gear 522, which rotates in the sealing rotational direction SD about the axis A415. The first connector 520b 1 transmits the rotational movement of the drive gear 522 to the first driven gear 526, which begins rotating. Because the driven shaft 524 and the first and second driven gears526 and 528 are fixed in rotation, this rotation of the first driven gear 526 causes the driven shaft 524 and the second driven gear 528 to rotate with the first driven gear 526 about the driven-shaft rotational axis A524. The second connector 520b2 transmits the rotational movement of the second driven gear 528 to the driven portion 452 of the weld actuator 450, causing the weld actuator 450 to rotate in about the axis A415. The first transmission-gear assembly 510 does not transmit the rotational movement of the motor output shaft to the driven shaft 405 of the tensioning-and-welding assembly 400.

[0058] As shown in Figures 3A and 3B, first and second housings 710 and 720 house and support certain components of the tensioning-and-welding assembly 400 and the first transmission-assembly gearing 510 and enable the tensioning-and-welding assembly 400 to pivot about the driven-gear-shaft rotational axis A524 between a tensioning-and-welding position and a strap-insertion position. Specifically, the housings 710 and 720 are pivotably mounted to the driven shaft 524 and configured to pivot relative to the support 300 — and particularly relative to the base 310 and the tensioning-and-welding plate 330 — under control of the hand lever 800 or a motor (depending on the embodiment) and about the driven-gear- shaft rotational axis A524. When the tensioning-and-welding assembly 400 is in the tensioning-and-welding position, as shown in Figures 3A-4B and 9A-9E, the outer surface of the tensioning-and-welding wheel 415 is adjacent to (and in this embodiment contacts) the toothed surface of the tensioning-and- welding plate 330 (or the upper surface of the upper layer of the strap if the strap has been inserted into the strapping tool 50). When the tensioning-and-welding assembly 400 is in the strap-insertion position, the tensioning-and-welding wheel 415 is spaced-apart from the toothed surface of the tensioning-and-welding plate 330 to enable two overlapping layers of the strap to be inserted between the tensioning-and-welding wheel 450 and the toothed surface. One or more springs or other biasing elements (not shown) bias the tensioning-and-welding assembly 400 to the tensioning-and-welding position.

[0059] The hand lever 800, which is shown in Figure 1A, is operably connected to the tensioning-and-welding assembly 400 — directly or via suitable linkages, gearing, and / or other components — and configured to move the tensioning-and-welding assembly 400 relative to the support 300 from the tensioning-and-welding position to the strap-insertion position. Specifically, the hand lever 800 is pivotable from a home position (shown in Figure 1A) spaced- apart from the handle section 150 of the housing 100 of the strapping tool 50 to an actuatedposition (not shown) closer to the handle section 150 to move the tensioning-and-welding assembly 400 from the tensioning-and-welding position to the strap-insertion position. In other embodiments, the motor is operably connected — via suitable gearing, linkages, and / or other components — to the tensioning-and-welding assembly and configured to pivot the tensioning- and-welding assembly from the tensioning-and-welding position to the strap-insertion position. In these embodiments, the strapping tool includes a suitable input device, such as a hand lever, a trigger, or a button, supported by the handle portion of the housing and actuatable to cause the motor to pivot the tensioning-and-welding assembly from the tensioning-and-welding position to the strap-insertion position.

[0060] The display assembly 1300, which is shown in Figures 1A and IB, includes a suitable display screen 1310 with a touch panel 1320. The display screen 1310 is configured to display information regarding the strapping tool 50 (at least in this embodiment), and the touch screen 1320 is configured to receive operator inputs such as a desired strap tension and desired weld cooling time. A display controller (not shown) may control the display screen 1310 and the touch panel 1320 and, in these embodiments, is communicatively connected to the controller 1600 to send signals to the controller 1600 and to receive signals from the controller 1600. Other embodiments of the strapping tool do not include a touch panel. Still other embodiments of the strapping tool do not include a display assembly. Certain embodiments of the strapping tool include a separate pushbutton panel instead of a touch panel beneath or integrated with the display screen.

[0061] The actuating assembly 1400, which is shown in Figures 1A and IB, is configured to receive operator input to start operation of the tensioning and sealing processes. In this example embodiment, the actuating assembly 1400 includes first and second pushbutton actuators 1410 and 1420 that, depending on the operating mode of the strapping tool 50, initiate the tensioning and / or sealing processes as described below. Other embodiments of the strapping tool 50 do not have an actuating assembly 1400 and instead incorporate its functionality into the display assembly 1300. For instance, in one of these embodiments two areas of the touch panel define virtual buttons that have the same functionality as mechanical pushbutton actuators.

[0062] The controller 1600, which is shown in Figure IB, 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 anysuitable 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 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 600, the display assembly 1300, the actuating assembly 1400, and the sensor(s) 1700 and configured to receive signals from and to control those components. The controller 1600 may also be communicatively connectable (such as via Wi-Fi, Bluetooth, nearfield 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.

[0063] The controller 1600 is configured to operate the strapping tool in one of three operating modes (as set by the operator): (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 600 to cause the tensioning-and-welding wheel 415 to rotate responsive to the first pushbutton actuator 1410 being actuated and maintained in its actuated state. The controller 1600 operates the motor 600 to cause the tensioning-and-welding wheel 415 axially move in a reciprocating manner to carry out the sealing process responsive to the second pushbutton actuator 1420 being actuated. In the semi-automatic operating mode, the controller 1600 operates the motor 600 to cause the tensioning-and-welding wheel 415 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 600 to cause the tensioning-and-welding wheel 415 axially move in a reciprocating manner to carry out the sealing process (without requiring additional input from the operator). In the automatic operating mode, the controller 1600 operates the motor 600 to cause the tensioning-and-welding wheel 415 to rotate responsiveto 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 600 to cause the tensioning-and- welding wheel 415 axially move in a reciprocating manner to carry out the sealing process (without requiring additional input from the operator).

[0064] The sensors 1700 include any suitable sensors, such as microswitches, optical sensors, ultrasonic sensors, magnetic position sensors, and the like, configured to detect the position of certain components of the strapping tool 50 and to send appropriate signals to the controller 1600. The sensors 1700 may include, for instance, one or more rocker-position sensors configured to detect when the tensioning-and-welding assembly 400 is in its tensioning-and- welding position and / or its strap-insertion position and one or more actuating-assembly sensors configured to detect actuation of the first and second pushbutton actuators 1410 and 1420.

[0065] The power supply is electrically connected to (via suitable wiring and other components) and configured to power several components of the strapping tool 50, including the motor 600, the display assembly 1300, the actuating assembly 1400, the controller 1600, and the sensor(s) 1700. The power supply is a rechargeable battery (such as a lithium-ion or nickel cadmium battery) in this example embodiment, though it may be any other suitable electric power supply in other embodiments. The power supply is sized, shaped, and otherwise configured to be received in the receptacle 122 defined by the rear housing section 120 of the housing 100. The strapping tool 50 includes one or more battery-securing devices (not shown) to releasably lock the power supply in place upon receipt in the receptacle. Actuation of a release device of the strapping tool 50 or the power supply unlocks the power supply from the housing 100 and enables an operator to remove the power supply from the receptacle 122.

[0066] Use of the strapping tool 50 to carry out a strapping process including: (1) a tensioning process in which the strapping tool 50 tensions strap around a load; and (2) a sealing process in which the strapping tool 50 attaches two overlapping portions of the strap to one another via friction welding is described below. The strapping tool 50 is in the automatic mode for the purposes of this example.

[0067] 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 hand lever 800and in doing so moves the tensioning-and-welding assembly 400 from its tensioning-and- welding position to its strap-insertion position. With the tensioning-and-welding assembly 400 in its strap-insertion position and while continuing to pull the hand lever 800, the operator introduces the overlapping upper and lower layers of the strap between the tensioning-and- welding wheel 415 and the tensioning-and-welding plate 330. The operator then releases the hand lever 800, which enables suitable biasing elements to force the tensioning-and-welding assembly 400 back toward its tensioning-and-welding position. Eventually, the outer surface of the tensioning-and-welding wheel 415 engages the top surface of the upper layer of the strap and force the bottom surface of the lower layer of strap against the toothed surface of the tensioning- and-welding plate 330.

[0068] The operator then actuates the first pushbutton actuator 1410 to initiate the strapping process. In response, the controller 1600 starts the tensioning process by controlling the motor 600 to begin rotating the motor output shaft in the tensioning rotational direction TD. As explained above, the transmission 500 transmits this rotational movement to the driven shaft 405 of the tensioning-and-welding assembly 400, which in turn causes the tensioning-and- welding wheel 415 to rotate. As the tensioning-and-welding wheel 415 rotates, it pulls the upper layer of the strap over the lower layer of the strap, thereby tensioning the strap around the load. The transmission 500 does not transmit rotational movement of the motor output shaft to the welding actuator 450 as this occurs. Throughout the tensioning process, the controller 1600 monitors the current drawn by the motor 600. 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 600, thereby completing the tensioning process.

[0069] The controller 1600 then automatically starts the sealing process by controlling the motor 600 to begin rotating the motor output shaft in the sealing rotational direction SD. As explained in detail above, the transmission 500 transmits this rotational movement to the welding actuator 450 and causes the welding actuator 450 to rotate. As also explained above, this rotation of the welding actuator 450 causes the tensioning-and-welding wheel 415 to axially move in a reciprocating manner along the axis A415 and relative to the tensioning-and-welding plate 330. The combination of the downward pressure the tensioning- and-welding wheel 415 exerts on the strap and the rapid reciprocation of the tensioning-and- welding wheel 415 locally melts the portions of the upper and lower strap layers together. After apreset period of time or a preset quantity of rotations of the motor output shaft, the controller 1600 controls the motor 600 to stop rotating the motor output shaft, completing the sealing process. After a certain period of time elapses, the controller 1600 stops the motor 600, thereby completing the sealing process. The melted portions 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.

[0070] The strapping tool of the present disclosure solves the above problems. First, using the tensioning-and-welding wheel to tension and weld the 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 of the support to be shorter in the longitudinal direction than the bases of traditional strapping tools, which enables the strapping tool of the present disclosure to be used for more applications (such as to strap curved loads with relatively small radii) than many traditional strapping tools.

[0071] In the example embodiment described above, a single motor is used to drive both the driven shaft during the tensioning process and the welding actuator during the sealing process. In other embodiments, the strapping tool includes separate tensioning and sealing motors. In these embodiments, the tensioning motor is operably connected to the tensioning-and- welding assembly to rotate the driven shaft during the tensioning process, and the sealing motor is operably connected to the welding actuator and configured to rotate the welding actuator during the sealing process. For instance, in one such embodiment, the first transmission-gear assembly operably connects the tensioning motor to the driven shaft of the tensioning-and- welding assembly so the tensioning motor can rotate the driven shaft, and the second transmission-gear assembly operably connects the sealing motor to the welding actuator of the tensioning-and-welding assembly so the sealing motor can rotate the welding actuator. In this embodiment, there is no connector / free wheel combination connecting the first and second transmission assemblies to enable selective driving of those assemblies based on the rotational direction of a single motor’s output shaft.

[0072] In the example embodiments described above, the tensioning-and-welding assembly is movable, and in particular pivotable, relative to the tensioning-and-welding plate tomake space for strap insertion. In other embodiments, the tensioning-and-welding assembly is stationary and the tensioning-and-welding plate is movable (such as pivotable) away from the tensioning-and-welding assembly to make space for strap insertion.

[0073] 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.

[0074] 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.

[0075] The relative locations of the tensioning-and-welding wheel and the driven- shaft-rotational axis about which the tensioning-and-welding wheel can pivot results in the tensioning-and-welding wheel exerting increased force against the tensioning-and-welding plate — and the strap between the two — as the strap tension increases during the tensioning process. In certain situations, if this force is too high it could negatively affect the sealing process, such as by making it difficult or impossible to axially move the tensioning-and-welding wheel. In certain embodiments, the strapping device includes a mechanical stop that is shaped, sized, oriented, positioned, and otherwise configured to prevent further downward movement of the tensioning-and-welding wheel once it reaches a particular height above the tensioning-and- welding plate. This also prevents the tensioning-and-welding wheel from exerting any force beyond a maximum force on the tensioning-and-welding plate and the strap between the tensioning-and-welding wheel and the tensioning-and-welding plate. This height is selected such that the maximum force is not so large so as to negatively affect the sealing process.

Claims

Claims1. A strapping device comprising: a tensioning-and-welding plate; a tensioning-and-welding wheel that is: rotatable relative to the tensioning-and-welding plate; and axially movable relative to the tensioning-and-welding plate between a first axial position and a second axial position; a rotatable welding actuator operably connected to the tensioning-and-welding wheel such that rotation of the welding actuator forces the tensioning-and-welding wheel to axially move in a reciprocating manner between the first and second axial positions; and at least one motor operably connected to the tensioning-and-welding wheel to rotate the tensioning-and-welding wheel and to the welding actuator to rotate the welding actuator.

2. The strapping device of claim 1, wherein the at least one motor comprises a single motor operably connected to the tensioning-and-welding wheel to rotate the tensioning-and- welding wheel and to the welding actuator to rotate the welding actuator.

3. The strapping device of claim 1, wherein the at least one motor comprises a first motor operably connected to the tensioning-and-welding wheel to rotate the tensioning-and- welding wheel and a second motor operably connected to the welding actuator to rotate the welding actuator.

4. The strapping device of claim 1, wherein the tensioning-and-welding wheel is rotatable about a rotational axis and is axially movable along the rotational axis.

5. The strapping device of claim 1, wherein a complete rotation of the welding actuator causes the tensioning-and-welding wheel to move between the first and second axial positions at least once.

6. The strapping device of claim 1, further comprising a driven shaft, wherein the tensioning-and-welding wheel is fixed in rotation with the driven shaft, wherein the at least onemotor is operably connected to the driven shaft to rotate the driven shaft to cause the tensioning- and-welding wheel to rotate, wherein the welding actuator is operably connected to the driven shaft to axially move the driven shaft in a reciprocating manner to cause the tensioning-and- welding wheel to axially move in a reciprocating manner between the first and second axial positions.

7. The strapping device of claim 6, further comprising spaced-apart first and second collars attached to and movable with the driven shaft, wherein the tensioning-and-welding wheel circumscribes the driven shaft and is positioned between the first and second collars.

8. The strapping device of claim 7, further comprising a first spacer between the first collar and a first actuating surface of the welding actuator and a second spacer between the second collar and a second actuating surface of the welding actuator.

9. The strapping device of claim 8, wherein the first actuating surface has a first undulating profile comprising a first peak and a first valley, wherein the second actuating surface has a second undulating profile comprising a second peak and a second valley, wherein the first and second actuating surfaces are opposite one another and rotationally offset such that the first peak is substantially aligned with the second valley and the first valley is substantially aligned with the second peak.

10. The strapping device of claim 9, wherein the tensioning-and-welding wheel is in the first axial position when the first spacer is adjacent the first valley and the second spacer is adjacent the second peak and is in the second axial position when the first spacer is adjacent the first peak and the second spacer is adjacent the second valley.

11. The strapping device of claim 10, wherein the welding actuator is rotatable relative to the first and second spacers.

12. The strapping device of claim 11, further comprising a first retainer fixed in rotation relative to the welding actuator and a second retainer fixed in rotation relative to the welding actuator, wherein the first retainer defines a first bore therethrough and the secondretainer defines a second bore therethrough, wherein the first spacer is received in and axially movable through the first bore, wherein the second spacer is received in and axially movable through the second bore.

13. The strapping device of claim 12, further comprising a housing to which the first and second retainers are fixedly mounted and to which the welding actuator is rotatably mounted.

14. The strapping device of claim 12, wherein rotation of the welding actuator causes simultaneous axial movement of the first and second spacers.

15. The strapping device of claim 14, wherein when the first spacer is adjacent the first valley and the second spacer is adjacent the second peak, rotation of the welding actuator causes the first actuating surface to exert a force on the first spacer that causes the first spacer to axially move the first collar, the second collar, the driven shaft, and the tensioning-and-welding wheel.

16. The strapping device of claim 15, wherein when the first spacer is adjacent the first peak and the second spacer is adjacent the second valley, rotation of the welding actuator causes the second actuating surface to exert a force on the second spacer that causes the second spacer to axially move the first collar, the second collar, the driven shaft, and the tensioning-and- welding wheel.

17. The strapping device of claim 16, wherein the tensioning-and-welding wheel is rotatable about a rotational axis and is axially movable along the rotational axis.

18. The strapping device of claim 17, further comprising a first spacer seat between the first collar and the first spacer and a second spacer seat between the second collar and the second spacer, wherein the first and second spacers are sized and positioned to engage the first and second spacer seats, respectively, as the welding actuator rotates to axially move the tensioning-and-welding wheel in a reciprocating manner between the first and second axial positions.

19. The strapping device of claim 17, wherein a complete rotation of the welding actuator causes the tensioning-and-welding wheel to move between the first and second axial positions at least once.

20. The strapping device of claim 1, further comprising: a first transmission-gear assembly operably connecting the at least one motor to the tensioning-and-welding wheel to rotate the tensioning-and-welding wheel; and a second transmission-gear assembly operably connecting the at least one motor to the wending actuator to rotate the welding actuator.

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