Strapping machine with edge-protector applicator

Abstract

Various embodiments of the present disclosure provide a strapping machine including an edge-protector applicator configured to position an edge protector on an upper corner of the load before strap is applied around the load.

Description

STRAPPING MACHINE WITH EDGE-PROTECTOR APPLICATORPriority

[0001] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 716,535, filed November 5, 2024, the entire contents of which is incorporated herein by reference.Field

[0002] The present disclosure relates to strapping machines for forming tensioned loops of strap around loads.Background

[0003] A strapping machine forms a loop of plastic strap (such as polyester or polypropylene strap), metal strap (such as steel strap), or paper strap around a load. Certain strapping machines include a support surface that supports the load, a strap chute that encircles the support surface, a strap reservoir (also called a strap accumulator or a slack box) storing strap in a slack state, a strapping head that forms the strap loop using strap drawn from the strap reservoir, a controller that controls the strapping head to strap the load, and a frame that supports these components. The strap reservoir is periodically replenished via strap drawn from a strap coil. A typical strapping head includes a strap-feeding assembly, a strap-tensioning assembly, and a strap-sealing assembly. The strap-feeding assembly is configured to feed strap from the strap reservoir into and around the strap chute and to retract the strap so it exits the strap chute and moves radially inwardly into engagement with the load with the excess being fed back into the strap reservoir. The strap-tensioning assembly is configured to tension the strap around the load. The strap-sealing assembly is configured to hold the leading end of the strap, to attach two portions of the strap together to form the tensioned strap loop, and to cut the tensioned strap loop from the remaining strap. Certain strapping machines have multiple strapping heads and respective strap chutes that define respective strap paths. These strapping machines areconfigured to simultaneously form multiple tensioned strap loops around a load using strap from separate respective strap supplies.

[0004] To strap the load, the strapping machine carries out a strapping process including a strap-feeding cycle, a strap-retraction cycle, a strap-tensioning cycle, and a strapsealing cycle. The strapping machine first carries out the strap-feeding cycle during which the strap-feeding assembly feeds strap (with the leading strap end first) through the strap-sealing assembly and into and around the strap chute until the leading strap end returns to the strapsealing assembly. The strapping machine then carries out the strap-retraction cycle during which the strap-sealing assembly holds the leading strap end while the strap-feeding assembly retracts the strap to pull the strap out of the strap chute and onto and around the load. The strapping machine then carries out the strap-tensioning cycle during which the strap-tensioning assembly tensions the strap to a designated strap tension. The strapping machine then carries out the strapsealing cycle during which the strap-sealing assembly attaches the leading strap end to another portion of the strap to form a strap joint, thereby forming a tensioned strap loop around the load, and cuts the tensioned strap loop from the remaining strap.

[0005] Press-type strapping machines apply a compressive force to the load to partially compress the load — such as to partially compress a stack of corrugated sheets — and / or to stabilize the load — such as to stabilize a load of stacked lumber — before strapping the load using one or more strapping heads. A typical press-type strapping machine includes a platen supported by the frame and vertically movable relative to the support surface and the load. The platen supports the strap-sealing assembly, and a strap dispenser adjacent the strapping machine supports the strap supply (e.g., a coil of strap) and the strap-feeding and strap-tensioning assemblies. An input chute connects the strap-feeding assembly to the strap-sealing assembly and provides a path for the strap to follow when fed from the strap-feeding assembly to the strapsealing assembly.

[0006] To carry out a strapping process, the platen first moves downward toward the support surface and into engagement with the load. As the platen continues moving downward, it applies a compressive force to the load. As this occurs, the controller monitors the compressive force the platen applies to the load and stops the platen once the applied compressive force reaches a target compressive force. At this point, the load is stabilized and / or partially compressed (depending on the application), and the controller then controls the strapping head(s)to strap the load as explained above. The platen then moves upward away from the support surface and the load to disengage the load and enable the load to be moved out of the strapping machine.

[0007] To protect the upper comers of the loads from damage, certain strapping machines include edge-protector applicators configured to position edge protectors on the upper corners of the loads so those edge protectors are positioned between the strap and the load after the tensioned strap loop is formed around the load.Summary

[0008] Various embodiments of the present disclosure provide a strapping machine including an edge-protector applicator configured to position an edge protector on an upper corner of the load before strap is applied around the load.Brief Description of the Figures

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

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

[0011] Figures 3A-3F are simplified elevational views of the strapping machine of Figure 1 applying edge protectors to the load, compressing the load, and strapping the load.

[0012] Figure 4A is a perspective view of the first and second edge-protector- application systems of the strapping machine of Figure 1.

[0013] Figure 4B is a cross-sectional perspective view of part of the strapping machine of Figure 1 taken along line 4B-4B of Figure 1.

[0014] Figure 5 is a perspective view of the edge-protector applicator of the first edge-protector-application system of Figure 4A.

[0015] Figure 6 is a perspective view of the edge-protector applicator of Figure 5 with the frame of the carriage-drive subassembly removed.

[0016] Figures 7 and 8 are perspective views of the carriage of the edge-protector applicator of Figure 5.

[0017] Figure 9 is a perspective view of the carriage of Figures 7 and 8 with the jaw subassembly separated from the frame subassembly.

[0018] Figure 10 is a perspective view of the jaw subassembly of Figure 9.

[0019] Figure 11 is a perspective view of the carriage of Figures 7 and 8 with the jaw subassembly in its raised position and the jaws of the jaw subassembly in their closed configuration.

[0020] Figures 12A-12F are cross-sectional side elevational views of part of the strapping machine of Figure 1 showing the edge-protector applicator of Figure 5 applying an edge protector to a load.

[0021] Figure 13A is a side elevational view of the carriage of Figures 7 and 8 with the jaw subassembly in its home position and the jaws of the jaw subassembly in their open configuration. The compression surface of the platen of the strapping machine of Figure 1 is shown for reference.

[0022] Figure 13B is a side elevational view similar to Figure 13 A but with the jaw subassembly in its raised position and the jaws of the jaw subassembly in their closed configuration. The compression surface of the platen of the strapping machine of Figure 1 is shown for reference.Detailed Description

[0023] 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 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 operablymounted, 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.

[0024] Figures 1-13B show one example embodiment of a press-type strapping machine 1 of the present disclosure and components thereof. The strapping machine 1 includes a frame 10, a load supporter 20, a platen 30, a platen actuator 35, multiple strap chutes 40 (only one of which is labeled), multiple strapping heads 50 (only one of which is labeled), multiple strap supplies 60 (only one of which is labeled), multiple input chutes 70 (only one of which is labeled), a first edge-protector-application system 100, a second edge-protector-application system 1100, and a controller C.

[0025] Generally, the strapping machine 1 is configured to carry out a strapping process by: (1) positioning substantially planar rectangular edge protectors above the upper corners of a load and beneath the platen 30 using the first and second edge-protector-application systems 100 and 1100; (2) lowering the platen 30 to compress the load; and (3) using each strapping head 50 to form an individual tensioned strap loop around the load. The process of forming the tensioned strap loops causes the edge protectors to bend into an L-shape.

[0026] Figures 3A-3F show a simplified illustration of the strapping machine 1 carrying out this strapping process. A load L is moved onto the load supporter 20 beneath the platen 30, as shown in Figure 3A. As also shown in Figure 3A, the first edge-protector- application system 100 positions a first edge protector EPl above a first upper comer of the load L and beneath the platen 30, and the second edge-protector-application system 1100 positions a second edge protector EP2 above a second upper comer of the load L and beneath the platen 30. The platen 30 descends into engagement with the load L and partially compresses the load L, as shown in Figure 3B. When this occurs, the first and second edge protectors EPl and EP2 are sandwiched between the platen 30 and the upper surface of the load L. Additionally, part of each edge protector extends over the side of the load. The strapping machine 1 carries out a strapfeeding cycle for each strapping head 50 by controlling the strapping head to feed strap S from the appropriate inlet chute 70, leading strap end first, into and around the appropriate strap chute 40 and then hold the leading strap end once it traverses the strap chute 40, as shown in Figure 3C. The strapping machine 1 carries out a strap-retraction cycle for each strapping head 50 by controlling the strapping head to retract the strap S such that it exits the strap chute 40 and movesradially inwardly into engagement with the load L, as shown in Figure 3D. As this occurs, the strap forces the edge protectors to bend into an L-shape, as also shown in Figure 3D. The strapping machine 1 carries out a strap-tensioning cycle for each strapping head 50 by controlling the strapping head to tension the strap S to a designated tension. The strapping machine 1 carries out the strap-sealing cycle for each strapping head 50 by controlling the strapping head to attach two portions of the strap S to one another to form a tensioned strap loop TSL around the load L and to cut the tensioned strap loop TSL from the remaining strap S, as shown in Figure 3E. The platen 30 ascends and disengages the load L, as shown in Figure 3F, completing the strapping process.

[0027] The frame 10 is configured to support some of the components of the strapping machine 1. In this example embodiment, the frame 10 includes a base 11, first and second spaced-apart upstanding legs 12 and 13, and a connector 14 that spans and connects the upper ends of the first and second legs 12 and 13. Although not labeled, the first and second legs 12 and 13 each include a vertically extending toothed rack to enable the platen 30 to move relative to the first and second legs 12 and 13 in a rack-and-pinion fashion, as described below. This is merely one example of a configuration of components that form the frame 1, and any other suitable configuration of any other suitable components may form the frame 1 in other embodiments.

[0028] The load supporter 20 is positioned atop the base 11, between the first and second legs 12 and 13, and below the connector 14 of the frame 1. The load supporter 20 is configured to support loads as they are compressed and strapped by and as they move through the strapping machine 1. In this example embodiment, load supporter 20 includes a driven roller conveyor, though it may include an undriven conveyor or any other suitable components in other embodiments.

[0029] The platen 30 is supported by the first and second legs 12 and 13 above the load supporter 20 and is vertically movable relative to the load supporter 20 so the platen 30 can adjust to loads of different heights and apply a compressive force to the loads. In this example embodiment, the platen 30 includes two rotatable pinions (not shown) fixed to opposite ends of a pinion shaft 32 such that the pinions and the pinion shaft 32 rotate together. The pinion shaft 32 extends between the first and second legs 12 and 13 such that one pinion meshes with the toothed rack in the first leg 12 and the other pinion meshes with the toothed rack in the secondleg 13. In this configuration, rotation of the pinions (which rotate together via their fixed connection to the pinion shaft 32) under control of the platen actuator 35 (described below) causes the pinions to climb or descend their respective toothed racks such that the platen 30 moves away from or toward the load supporter 20 (i.e., upward or downward, as described in more detail below). The platen 30 also includes one or more substantially planar, parallel compression surfaces 31 on its underside for engaging and applying the compressive force to the load.

[0030] The platen actuator 35 includes any suitable actuator — such as an electric, pneumatic, or hydraulic motor — operably connected to the platen 30 and configured to move the platen 30 relative to the first and second legs 12 and 13 toward and away from the load supporter 20 (i.e., downward and upward). In this example embodiment, the platen actuator 35 is operably connected to the pinions and the pinion shaft 32 of the platen 30 via gearing such that rotation of an output shaft of the platen actuator 35 results in rotation of the pinion shaft 32 and the pinions and vertical movement of the platen 30. In one example embodiment, an output gear of the gearing is meshed with one of the pinions such that rotation of the output gear caused by rotation of the output shaft of the platen actuator 35 directly causes that pinon to rotate, which in turn causes the pinion shaft 32 and the other pinion to rotate. Rotating the output shaft of the platen actuator 35 in one direction results in movement of the platen 30 away from the load supporter 20, and rotation of the output shaft in the opposite direction results in movement of the platen 30 toward the load supporter 20. This is merely one example embodiment of the platen actuator, and any suitable actuator may be employed. Additionally, any other suitable manner of controlling vertical movement of the platen 30 may be employed (e.g., hydraulic or pneumatic cylinders, belt-and-pulley assemblies, and the like), as the rack-and-pinion configuration is merely one example embodiment.

[0031] Each strap chute 40 encircles an upper surface of the load supporter 20 and defines a strap path that the strap traverses when fed into and through the strap chute 40 and from which the strap is removed when retracted onto the load. As shown in Figure 3A for an example strap chute, each strap chute 40 includes spaced-apart first and second upstanding legs 41 and 42, an upper connecting portion 43 that spans the first and second legs 41 and 42 and is positioned in the platen 30, and a lower connecting portion 44 that spans the first and second legs 41 and 42 and is positioned in the load supporter 20.

[0032] A strapping area is defined between the load supporter 20 and the platen 30 and is encircled by each strap chute 40. In this example embodiment, the radially inward walls of each strap chute 40 are formed from multiple gates that are spring biased to a closed position that enables the strap to traverse the strap path when fed through the strap chute 40. When the strapping head 50 later exerts a sufficient pulling force on the strap to retract the strap, the pulling force overcomes the biasing force of the springs and causes the gates to pivot to an open position, thereby releasing the strap from the strap chute 40 so the strap engages the load as the strapping head 50 continues to retract the strap. In other embodiments, the radially inward walls of the strap chute are configured to be actively opened, such as under control of a suitable actuator.

[0033] Each strapping head 50 is configured to form a tensioned strap loop around the load by feeding the strap through one of the strap chutes 40, holding the leading end of the strap while retracting the strap to remove it from the strap chute 40 so it engages the load, tensioning the strap around the load to a designated tension, connecting the leading strap end to another portion of the strap, and cutting the strap from the strap supply. In this example embodiment, the strapping head 50 is a modular strapping head including independently removable and replaceable feed, tensioning, and sealing assemblies 51, 52, and 53. The strapfeeding assembly 51, which is configured to feed and retract the strap, and the strap-tensioning assembly 52, which is configured to tension the strap, are mounted to a frame of the strap supply 60. The platen 30 supports the strap-sealing assembly 53, which is configured to hold the leading strap end, cut the strap from the strap supply, and connect two portions of the strap to one another. That is, in this example embodiment, the strap-feeding and strap-tensioning assemblies 51 and 52 are located remote from the strap-sealing assembly 53 (though in other embodiments the strap-feeding and / or strap-tensioning assemblies 51 and 52 may be supported by the frame 1, the platen 30, or any other suitable component of the strapping machine 1). In this example embodiment, each strapping head is associated with and configured to feed strap into a different one of the strap chutes.

[0034] This is merely one example strapping head, and the strapping machine 1 may include any suitable modular strapping head or non-modular strapping head (i.e., a strapping head that is not comprised of independently removable and replaceable feed, tensioning, and sealing modules). The manner of attaching the two portions of the strap to one another dependson the type of strapping machine and the type of strap. Certain strapping machines configured for plastic strap or paper strap include strapping heads with friction welders, heated blades, or ultrasonic welders configured to attach the two portions of the strap to one another. Some strapping machines configured for plastic strap or metal strap include strapping heads with jaws that mechanically deform (referred to as “crimping” in the industry) or cut notches into (referred to as “notching” in the industry) a seal element positioned around the two portions of the strap to attach them to one another. Other strapping machines configured for metal strap include strapping heads with punches and dies configured to form a set of mechanically interlocking cuts in the two portions of the strap to attach them to one another (referred to in the strapping industry as a “sealless” attachment). Still other strapping machines configured for metal strap include strapping heads with spot, inert-gas, or other welders configured to weld the two portions of the strap to one another.

[0035] Each strap supply 60 includes a suitable frame (not labeled) that supports the strap-feeding assembly 51 and the strap-tensioning assembly 52 of the associated strapping head 50 along with a coil of strap.

[0036] Each inlet chute 70 connects the strap-feeding assembly 51 of one of the strapping heads 50 to the strap chute 40 associated with that strapping head 50. In this example embodiment, each inlet chute 70 is a flexible tubular member that has an arch shape and defines a strap path between the strap-feeding assembly 51 and the strap-sealing assembly 53 of the associated strapping head 50.

[0037] The first edge-protector-application system 100, which is shown in Figures 4 A and 4B, is configured to store a supply of edge protectors and to, during a strapping process, retrieve one of those edge protectors and position it above an upper corner of the load. The first edge-protector-application system 100 is attached to the platen 30 and includes an edge-protector magazine 200 and an edge-protector applicator 300.

[0038] The edge-protector magazine 200 is attached to the platen 30 and is configured store a supply of substantially planar, rectangular edge protectors EP and to deliver individual edge protectors from the stack to the edge-protector applicator 300. The edgeprotector magazine 200 includes a magazine frame 210 configured to receive and store multiple edge protectors EP stacked atop one another. The magazine frame 210 supports a delivery assembly 220 operable to push the bottom edge protector EP in the stack of edge protectors EPout of a discharge slot (not labeled) and in a first direction DI toward the edge-protector applicator 300 to enable the edge-protector applicator 300 to grip the edge protector EP and then move it in a second direction D2 (which is transverse and, here, perpendicular to the first direction DI) to position it above an upper corner of the load. The edge-protector magazine 200 may be any suitable device configured to deliver an edge protector to the edge-protector applicator, such as (but not limited to) those described in European Patent No. 2,700,577; European Patent No. 2,778,075; and European Patent No. 2,778,076.

[0039] The edge-protector applicator 300 is configured to receive an individual edge protector EP from the edge-protector magazine 200 and to move it above an upper comer of a load. The edge-protector applicator 300 includes a carriage-drive subassembly 400 and a carriage 500.

[0040] The carriage-drive subassembly 400, which is best shown in Figures 5 and 6, is configured to move the carriage 500 in the second direction D2. The carriage-drive subassembly 400 includes a frame 405, a rail 410, a first carriage stop 412, a second carriage stop 414, a drive gear pulley 420, a first idler gear pulley 424, a second idler gear pulley 426, a first tension pulley 428, a second tension pulley 430, a drive belt 435, a belt connector 440, a carriage actuator 450, a transmission 460, and a carriage sensor 490.

[0041] The frame 405 serves as a support for some or all of the other components of the carriage-drive subassembly 400 and is sized and shaped accordingly. The elongated rail 410 is attached to the frame 405 in any suitable manner, such as via fasteners, and extends substantially parallel to the second direction D2. The first and second carriage stops 412 and 414 — which are rubber bumpers in this example embodiment but may be any suitable components in other embodiments — are attached to the frame 405 in any suitable manner near opposite ends of the rail 410. The drive gear pulley 420 is attached to the frame 405 above the rail 410 in a manner that enables the drive gear pulley 420 to rotate relative to the frame 405. The first and second idler gear pulleys 424 and 426 are attached to the frame 405 near opposite ends of the rail 410 and between the rail 410 and the drive gear pulley 420 in a manner that enables the first and second idler gear pulleys 424 and 426 to rotate relative to the frame 405. The drive belt 435 extends around the drive gear pulley 420 and the first and second idler gear pulleys 424 and 426. The first and second tension pulleys 428 and 430 are attached to the frame 405 in a manner that enables them to rotate relative to the frame 405. The first and second tension pulleys428 and 430 engage the drive belt 435 and maintain tension in the drive belt 435. The belt connector 440 is fixedly attached to a lower portion of the drive belt 435 between the bottoms of the first and second idler gear pulleys 424 and 426 such that the belt connector moves with the drive belt 436 between those idler gear pulleys.

[0042] The drive gear pulley 420 is drivingly engaged to the drive belt 435 such that rotation of the drive gear pulley 420 causes the drive belt to move around the drive gear pulley 420 and the first and second idler gear pulleys 424 and 426. The carriage actuator 450 is operably connected to the drive gear pulley 420 via the transmission 460 and is configured to rotate the drive gear pully 420 to cause movement of the drive bent 435. The carriage actuator 450 includes an electric motor in this example embodiment but may include any other suitable actuator (such as a hydraulic or pneumatic actuator) in other embodiments. The transmission 460 includes gearing in this example embodiment but may include any other suitable components (or not be included at all) in other embodiments.

[0043] The carriage sensor 490 is any suitable sensor, such as an optical position sensor, configured to detect the carriage 500 when the carriage 500 is at its home position. In this example embodiment, the carriage sensor 490 is attached to the platen 30, though in other embodiments it is attached to the frame 405 of the carriage-drive subassembly 400.

[0044] The carriage-drive subassembly 400 is attached to the platen 30 near the edge-protector magazine 200. The carriage-drive subassembly 400 is positioned near the compression surfaces 31 and, as best shown in Figure 4B, is positioned within a cavity defined in the platen 30 such that the carriage-drive subassembly 400 does not extend below the compression surfaces 31, as best shown in Figures 13A and 13B.

[0045] The carriage 500, which is best shown in Figures 7-11, is configured to receive an edge protector EP from the magazine 200 and to clamp that edge protector EP in preparation for moving toward the load. The carriage 500 includes a jaw subassembly 600 configured to receive and clamp the edge protector EP and a frame subassembly 700 configured to support the jaw subassembly 600.

[0046] The jaw subassembly 600 includes a jaw actuator 610, a lower jaw 620, an upper jaw 630, a second load sensor 640, a bracket 650, a first mount 652, and a second mount 654.

[0047] The lower jaw 620 includes a substantially planar lower-jaw plate 622, a lower-jaw arm 624 extending upward from the lower-jaw plate 622, and a lower-jaw rail 626 fixedly attached to the lower-jaw arm 624. The lower jaw plate 622 includes an upper surface (not labeled) that functions as a clamping surface. Similarly, the upper jaw 630 includes a substantially planar upper-jaw plate 632, an upper-jaw arm 634 extending upward from the upper-jaw plate 632, and an upper-jaw rail 636 fixedly attached to the upper-jaw arm 634. The upper jaw plate 630 includes a lower surface (not labeled) that functions as a clamping surface and that is opposite the clamping surface of the lower jaw plate 622. The jaw actuator 610 includes a body defining two substantially parallel channels in which the lower-jaw rail 626 and the upper-jaw rail 636 are received. The jaw actuator 610 is configured to maintain the position of the upper jaw 630 and is configured to move the lower jaw 620 relative to the upper jaw 630 between a lower position shown in Figures 7-10 and an upper position shown in Figure 11. The vertical space between the lower-jaw plate 622 and the upper-jaw plate 632 is larger when the lower jaw 620 is in the lower position than when it is in the upper position. The jaws are in an open configuration when the lower jaw 620 is in the lower position and in a closed configuration when the lower jaw 620 is in the upper position. In this example embodiment, the jaw actuator 610 is an electric gripper, though it may be any suitable type of electric, pneumatic, hydraulic, or other actuator in other embodiments.

[0048] In certain embodiments, one or both clamping surfaces of the lower jaw plate and the upper jaw plate include high-friction material, such as a rubber material, and / or teeth to enable these components to better grip the edge protector.

[0049] The second load sensor 640 is any suitable sensor, such as an optical position sensor, configured to detect the load. In this example embodiment, the second load sensor 640 is attached to the jaw actuator 610, though in other embodiments it is attached to another component of the jaw subassembly.

[0050] The bracket 650 includes a first portion and a second portion oriented in an L-shape. The first portion is fixedly attached to the jaw actuator 610. The first mount 652 and the second mount 654 each define an elongated semicircular channel and are fixedly attached to the second portion of the bracket 650 such that the channels are substantially parallel.

[0051] The frame subassembly 700 includes a frame 710, a guide 720 fixedly attached to the frame 710, a connector 730 fixedly attached to the frame 710, a sensed element740 fixedly attached to the frame 710, a support 750 fixedly attached to the frame 710 and including spaced-apart circular first and second rails 752 and 754, a stop support 760 fixedly attached to the bottoms of the first and second rails 752 and 754 and including first and second stops 762 and 764, a spring 770, and a first load sensor 790. The first load sensor 790 is any suitable sensor, such as an optical position sensor, configured to detect the load. In this example embodiment, the first load sensor 790 is attached to the frame 710, though in other embodiments it is attached to another component of the frame subassembly.

[0052] The jaw subassembly 600 is movably mounted to the frame subassembly 700. Specifically, the first and second rails 752 and 754 extend through the channels defined through the first and second mounts 652 and 654 of the jaw subassembly 600, respectively. Accordingly, the jaw subassembly 600 is slidably mounted to the frame subassembly 700 and vertically movable relative to the frame subassembly 700 between a home (or lower) position — best shown in Figures 7, 8, and 13A — and a raised position — best shown in Figures 11 and 13B. When the jaw subassembly 600 is in the home position, the first and second mounts 652 and 654 rest on the first and second stops 762 and 764, respectively. The weight of the jaw subassembly 600 and the spring 790 — which extends between a first fastener 766 attached to the stop support 760 and a second fastener (not shown) attached to the bracket 650 — bias the jaw assembly 600 to the home position. When the jaw subassembly 600 is in the raised position, the first and second mounts 652 and 654 are spaced-apart from the first and second stops 762 and 764, respectively.

[0053] The rail 410 of the carriage-drive subassembly 400 extends through a correspondingly shaped channel defined in the guide 720 of the frame subassembly 700 such that the carriage 500 is slidably mounted to the carriage-drive subassembly 400. The connector 730 is fixedly attached to the belt connector 440 (such as via suitable fasteners) such that the carriage 500 and the belt connector 440 move together in the second direction D2 as the drive gear pulley 420 rotates. Accordingly, the carriage actuator 450 is operably connected to the carriage 500 and configured to move the carriage 500 in the second direction D2. The sensed element 740 is positioned to be detected by the carriage sensor 490 when the carriage 500 is in the home position.

[0054] Figures 13 A and 13B show the positions of the components of the edgeprotector applicator 300 relative to the compression surfaces 31 of the platen 30. As shown in Figure 13A, when the jaw subassembly 600 is in its home position and the lower and upper jaws620 and 630 are in their open configuration, the entire lower-jaw plate 622 and at least part of the upper-jaw plate 632 are positioned below the compression surfaces 31 such that an edge protector can be received between the jaw plates. As shown in Figure 13B, when the jaw subassembly 600 is in its raised position and the lower and upper jaws 620 and 630 are in their closed configuration, none of the components of the jaw subassembly 600 extend below the compression surfaces 31 and they are all positioned in the cavity defined in the platen 30. The ability of the jaw subassembly 600 to move vertically relative to the frame subassembly 700 in this manner prevents the jaw subassembly 600 from being damaged if, for instance, the lower jaw 620 or the jaw actuator 610 becomes trapped between the upper surface of the load and the compression surfaces 31 during compression. Instead of damaging the jaw subassembly 600 or the load in this scenario, the jaw subassembly 600 is slid into the platen 30 and out of the way.

[0055] The second edge-protector-application system 1100, which is shown in Figures 4A and 4B, is configured to store another supply of edge protectors and to, during the strapping process, retrieve one of those edge protectors and position it above another upper corner of the load. The second edge-protector-application system 1100 is attached to the platen 30 and includes an edge-protector magazine 1200 and an edge-protector applicator 1300 that includes a carriage-drive subassembly 1400 configured to move a carriage 1500. The components of the second edge-protector-application system 1100 are substantially similar to those of the first edge-protector-application system 100 and are not separately described for brevity.

[0056] The controller C 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 can include any suitable processing device such as, but not limited to, a general-purpose processor, a special-purpose processor, a digital-signal processor, one or more microprocessors, one or more microprocessors in association with a digital-signal processor core, one or more application-specific integrated circuits, one or more field-programmable gate array circuits, one or more integrated circuits, and / or a state machine. The memory device may include any suitable memory device such as, but not limited to, readonly 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 removablememory, magneto-optical media, and / or optical media. The memory device stores instructions executable by the processing device to control operation of the strapping machine 1.

[0057] The controller C is communicatively and operably connected to the platen actuator 35, the strapping heads 50, the magazines 200 and 1200, the carriage actuators of the carriage-drive subassemblies 400 and 1400, the carriage sensors of the carriage-drive subassemblies 400 and 1400, the jaw actuators of the jaw subassemblies of the carriages 500 and 1500, the second load sensors of the jaw subassemblies of the carriages 500 and 1500, and the first load sensors of the frame subassemblies of the carriages 500 and 1500 to receive signals from and to control those components.

[0058] Operation of the strapping machine 1 to carry out a strapping process is now described in conjunction Figures 3A-3F and Figures 12A-12F. A load L is moved to the strapping area of the strapping machine 1, as shown in Figures 3A and 12A. The first and second edge-protector-application systems 100 and 1100 then position edge protectors EP above the upper comers of the load L. This process is now described for the first edge-protector-application system 100, and the substantially similar (albeit mirrored) process for the second edge-protector- application system 1100 is not described for brevity. As shown in Figure 12A, the controller C controls the delivery assembly 220 of the magazine 200 to push the bottom edge protector EP from the stack of edge protectors (best shown in Figure 4A) out of the discharge slot and in the first direction DI such that the edge protector EP is positioned between the lower- and upperjaw plates 622 and 632 of the lower and upper jaws 620 and 630 of the jaw subassembly 600 of the carriage 500, which are in the open configuration as shown in Figure 12A. The controller C then controls the jaw actuator 610 to move the lower jaw 620 to the upper position such that the lower and upper jaws 620 and 630 are in the closed configuration and the edge protector EP is sandwiched between the lower- and upper- jaw plates 622 and 632, as shown in Figure 12B.

[0059] The controller C then controls the carriage actuator 450 to move the carriage 500 in the second direction D2. Eventually, the first load sensor 790 detects the upper surface of the load L and sends an appropriate signal indicating this to the controller C. In response, the controller C continues to control the carriage actuator 450 to move the carriage 500 in the second direction D2 for a predetermined period before stopping the carriage actuator 450. At this point, the approximate center of the edge protector EP is positioned above the upper comer of the load L, as shown in Figure 12C. The controller C then controls the platen actuator 35 to begin movingthe platen 30 toward the load L. As this occurs, the compression surfaces 31 of the platen 30 contact the upper surface of the edge protector EP and the load L such that the edge protector EP is sandwiched between the compression surfaces 31 and the upper surface of the load L, as shown in Figures 3B and 12D. The controller C continues lowering the platen 30 to compress the load before stopping the platen 30, as shown in Figure 3C. In certain embodiments, the controller C monitors the amount of compressive force the platen 30 applies to the load L, such as via a compression sensor, and stops the platen 30 once the applied compressive force reaches a predefined value. In other embodiments, the controller C monitors the position of the platen 30, such as via a distance sensor, and stops the platen 30 once the platen 30 is a predetermined distance above the load supporter 20.

[0060] After the compression surfaces 31 of the platen 30 engage the edge protector EP, the controller C controls the jaw actuator 610 to move the lower jaw 620 back to lower position — and the upper and lower jaws 630 and 620 to their open configuration — to release the edge protector EP, as shown in Figure 12E. The controller C then controls the carriage actuator 450 to move the carriage 500 back to its home position, as shown in Figure 12F. The controller C controls the strapping head 50 to begin carrying out the strap-feeding cycle. Specifically, the controller C controls the strap-feeding assembly 51 to begin feeding strap S leading strap end LE first through the input chute 70, through the strap-sealing assembly 53, and into and around the strap chute 40, as shown in Figure 3C. The controller C the controls the strap-feeding assembly 51 to retract the strap S so that it exits the strap chute 40 and moves radially inwardly and engages the load L. As this occurs, the strap forces the edge protectors to bend into an L-shape. Figure 3D shows the strapping machine 1 after the strap S has exited the strap chute 40 and engaged the load L. The controller C controls the strap-tensioning assembly 52 to tension the strap S around the load to a designated tension and controls the strap-sealing assembly 53 to attach two portions of the strap S to one another and to cut the strap S from the strap supply to form a tensioned strap loop TSL around the load L and complete the strapping process. Figure 3E shows the strapping machine 1 after the strap S has been tensioned, sealed, and cut to form the tensioned strap loop TSL. The controller C controls the platen actuator 35 to raise the platen 30 until it disengages the load L so the load L can be moved out of the strapping machine 1. Figure 3F shows the strapping machine 1 after the load L has been moved.

[0061] In the embodiment described above, the jaw actuator is configured to maintain the position of the upper jaw and to raise the lower jaw toward the upper jaw to switch the upper and lower jaws from the open configuration to the closed configuration, and vice- versa. In other embodiments, the jaw actuator is configured to maintain the position of the lower jaw and to lower the upper jaw toward the lower jaw to switch the upper and lower jaws from the open configuration to the closed configuration, and vice-versa. In further embodiments, the jaw actuator is configured to raise the lower jaw toward the upper jaw and lower the upper jaw toward the lower jaw to switch the upper and lower jaws from the open configuration to the closed configuration, and vice versa. Put differently, depending on the embodiment, the jaw actuator is configured to move only one of or both of the jaws when switching them between the open and closed configurations.

[0062] In certain embodiments, the strapping machine includes an edge-protector sensor configured to detect the presence of an edge protector between the lower- and upper-jaw plates of the lower and upper jaws. In certain of these embodiments, the controller is configured to move the lower jaw to its upper position — and therefore the upper and lower jaws to the closed configuration — only in response to receiving a signal from the edge-protector sensor indicating that it detected the presence of an edge protector between the lower- and upper-jaw plates of the lower and upper jaws. In various embodiments, if the controller does not receive such a signal from the edge-protector sensor within a certain period after the magazine has attempted to deliver an edge protector to the edge-protector applicator, the controller controls an output device (such as a display device of the strapping machine) to indicate an error message.

[0063] In various embodiments, the strapping machine includes a jaw sensor configured to detect when a distance that is less than the thickness of a single edge protector separates the lower- and upper-jaw plates of the lower and upper jaws and to send a corresponding signal to the controller. If the jaw sensor detects this, then an edge protector is not positioned between the lower and upper jaws. In certain of these embodiments, if the controller receives this signal from the jaw sensor, the controller is configured to stop the edge-protector positioning process and not control the carriage actuator to move the carriage in the second direction toward the load. The controller may also control an output device (such as a display device of the strapping machine) to indicate an error message.

Claims

Claims1. A strapping machine comprising: a load supporter; a platen above the load supporter and vertically movable toward and away from the load supporter; a carriage mounted to the platen and horizontally movable relative to the platen, the carriage comprising: a lower jaw comprising a lower clamping surface; an upper jaw comprising an upper clamping surface positioned above the lower clamping surface; and a jaw actuator configured to switch the lower jaw and the upper jaw between an open configuration in which a first distance separates the lower and upper clamping surfaces and a closed configuration in which a second distance separates the lower and upper clamping surfaces, wherein the first distance is greater than the second distance; and a magazine mounted to the platen and configured to, when the lower jaw and the upper jaw are in the open configuration, move an edge protector from the magazine to a location between the lower and upper clamping surfaces.

2. The strapping machine of claim 1, wherein the platen comprises a compression surface facing the load supporter, wherein at least part of the carriage is vertically movable relative to the platen between a home position and a raised position.

3. The strapping machine of claim 2, wherein the lower and upper clamping surfaces of the lower and upper jaws, respectively, are below the compression surface when the at least part of the carriage is in the home position and when the lower and upper jaws are in the open configuration.

4. The strapping machine of claim 3, wherein the lower and upper clamping surfaces of the lower and upper jaws, respectively, are below the compression surface when the at leastpart of the carriage is in the home position and when the lower and upper jaws are in the closed configuration.

5. The strapping machine of claim 4, wherein the lower and upper clamping surfaces of the lower and upper jaws, respectively, are not below the compression surface when the at least part of the carriage is in the raised position and when the lower and upper jaws are in the closed configuration.

6. The strapping machine of claim 5, further comprising a spring biasing the at least part of the carriage to the home position.

7. The strapping machine of claim 5, wherein the platen defines a cavity above the compression surface, wherein the carriage is partially positioned within the cavity when the at least part of the carriage is in the home position, wherein the carriage is entirely positioned within the cavity when the at least part of the carriage is in the raised position.

8. The strapping machine of claim 7, further comprising a carriage-drive subassembly mounted to the platen and configured to move the carriage relative to the platen.

9. The strapping machine of claim 8, wherein the carriage-drive subassembly comprises a carriage actuator operably connected to the carriage to move the carriage relative to the platen.

10. The strapping machine of claim 9, wherein the entire carriage-drive subassembly is positioned within the cavity and does not extend below the compression surface.

11. The strapping machine of claim 10, wherein the jaw actuator is configured to translate at least one of the lower jaw and the upper jaw to switch the lower jaw and the upper jaw between the open configuration and the closed configuration.

12. The strapping machine of claim 9, wherein the carriage-drive subassembly further comprises a drive gear pulley and a drive belt operably connecting the drive gear pulley to thecarriage, wherein the carriage actuator is operably connected to the drive gear pulley to rotate the drive gear pulley to cause the carriage to move relative to the platen.

13. The strapping machine of claim 1, wherein the jaw actuator is configured to translate at least one of the lower jaw and the upper jaw to switch the lower jaw and the upper jaw between the open configuration and the closed configuration.

14. The strapping machine of claim 1, further comprising a carriage-drive subassembly mounted to the platen and configured to move the carriage relative to the platen.

15. The strapping machine of claim 14, wherein the carriage-drive subassembly comprises a carriage actuator operably connected to the carriage to move the carriage relative to the platen.

16. The strapping machine of claim 15, wherein the platen comprises a compression surface facing the load supporter, wherein the platen defines a cavity above the compression surface, wherein the carriage is at least partially positioned within the cavity, wherein the entire carriage-drive subassembly is positioned within the cavity and does not extend below the compression surface.

17. The strapping machine of claim 16, wherein the lower and upper clamping surfaces of the lower and upper jaws, respectively, are below the compression surface when the lower and upper jaws are in the open configuration and when the lower and upper jaws are in the closed configuration.

18. The strapping machine of claim 1, wherein the platen comprises a compression surface facing the load supporter, wherein the lower and upper clamping surfaces of the lower and upper jaws, respectively, are below the compression surface when the lower and upper jaws are in the open configuration and when the lower and upper jaws are in the closed configuration.

19. The strapping machine of claim 18, wherein the jaw actuator is configured to raise the lower jaw toward the upper jaw to move the lower and upper jaws from the openconfiguration to the closed configuration and to lower the lower jaw away from the upper jaw to move the lower and upper jaws from the closed configuration to the open configuration.

20. The strapping machine of claim 1, further comprising a controller configured to: control vertical movement of the platen, control horizontal movement of the carriage, and control the lower and upper jaws to switch between the open and closed configurations.

Images