Patent Application
20250178763
The invention generally relates to wrapping loads with paper-based packaging material through relative rotation of loads and a paper-based packaging material dispenser.
Various packaging techniques have been used to build a load of unit products and subsequently wrap them for transportation, storage, containment and stabilization, protection and waterproofing. One system uses wrapping machines to stretch, dispense, and wrap a polymer-based packaging material, e.g., film, around a load. The polymer-based packaging material may also be pre-stretched before it is applied to the load. Wrapping can be performed as an inline, automated packaging technique that dispenses and wraps packaging material in a stretch condition around a load on a pallet to cover and contain the load. Stretch wrapping, whether accomplished by a turntable, rotating arm, vertical rotating ring, or horizontal rotating ring, typically covers the four vertical sides of the load with a stretchable packaging material such as polyethylene packaging material. In each of these arrangements, relative rotation is provided between the load and the packaging material dispenser to wrap packaging material about the sides of the load.
Worldwide sensitivity to sustainability has increased interest in non-polymer alternatives for wrapping loads. Initial candidates include relatively standard kraft paper to various alternatives that attempt to include some level of stretchability to accommodate the irregularity of virtually all wrapped loads and their fit to a pallet. Irrespective of the stretchability of such non-polymer alternatives, however, the degree of stretchability is generally less than that provided by polymer films.
Wrapping a load with materials exhibiting limited stretchability, however, presents several unique concerns relative to polymer films. Spiral wrapping, where a packaging material web is moved in a direction parallel to the axis of rotation concurrently with rotating around the axis of rotation, can cause non-stretchable packaging materials such as paper-based packaging materials to exhibit undesirable characteristics. The relative movement of a packaging material web relative to rotation is generally referred to as pitch, and is defined specifically as the relative web travel along the axis of rotation per load revolution. It has been observed that any change in pitch during a wrapping process will generally create an imbalance on the forces exhibited on the opposing edges of the web of packaging material, and cause puckering on one edge of the web as it is wrapped around the load. In addition, where the girth of a load changes at different elevations, force imbalances may also occur and cause similar undesirable effects.
In addition, the handling of a packaging material web of a non-stretchable material, e.g., at the beginning and end of a wrap cycle, can also present challenges that are unique as compared to conventional polymer-based stretch wrapping materials.
The invention addresses these and other problems associated with the art by providing an apparatus and method for wrapping a load with paper-based packaging material. In some embodiments, a paper-based packaging material holder that is movable to a position adjacent a load is used to hold a leading end of a web of paper-based packaging material at the beginning of a wrap cycle. Further, in some embodiments, a bottom edge of a paper-based packaging material is gathered together to form a rope, e.g., in order to wrap around a pallet. In addition, in some embodiments, a trailing end of a web of paper-based packaging material is adhered to a load by pressing the trailing end against the load both upstream and downstream of a last corner of the load.
Therefore, consistent with one aspect of the invention, an apparatus for wrapping a load may include a paper-based packaging material dispenser configured to dispense a web of paper-based packaging material to the load, a rotational drive configured to generate relative rotation between the paper-based packaging material dispenser and the load about an axis of rotation during a wrap cycle, and a paper-based packaging material holder. The paper-based packaging material holder includes a clamp including a downwardly-facing opening configured to receive a leading end of the web of paper-based packaging material and hold the leading end of the web of paper-based packaging material during at least a portion of the wrap cycle, and an arm supporting the clamp, the arm being biased to a first position that is separated from a side of the load, and the arm being movable to a second position that positions the clamp against the side of the load in response to tension in the web of paper-based packaging material during the relative rotation when the leading end of the web of paper-based packaging material is held by the clamp.
In some embodiments, the paper-based packaging material holder further includes an arm support configured to support the arm, the arm support configured to maintain a substantially constant rotational position about the axis of rotation relative to the load during wrapping. In addition, some embodiments may further include a platen configured to rotate about the axis of rotation, and a platen support configured to move the platen in the direction of the axis of rotation to engage with a top of the load during wrapping, and the arm support is mounted to the platen.
Also, in some embodiments, the arm support is configured to support the arm for rotation about a pivot axis, and the pivot axis is substantially parallel to the axis of rotation. Further, in some embodiments, the clamp is a first clamp, and the apparatus further includes a second clamp that is movable in a direction along the axis of rotation and configured to support the leading end of the web of paper-based packaging material prior to the wrap cycle. In some embodiments, the second clamp is configured to hold a trailing end of the web of paper-based packaging material at an end of the wrap cycle. In addition, in some embodiments, the second clamp is configured to move in the direction along the axis of rotation with the paper-based packaging material dispenser.
Some embodiments may also include a controller, and the controller is configured to control the apparatus to, proximate a start of the wrap cycle, move the leading end of the web of paper-based packaging material in the direction along the axis of rotation while being held by the second clamp such that the leading end of the web of paper-based packaging material is received within the opening of the first clamp, actuate the first clamp to hold the leading end of the web of paper-based packaging material after the leading end of the web of paper-based packaging material is received in the opening of the first clamp, and release the second clamp after actuating the first clamp.
In some embodiments, at least one layer of the web of paper-based packaging material overwraps the clamp during the wrap cycle, and the arm is movable in a direction along the axis of rotation to withdraw the clamp from the leading end of the web of paper-based packaging material proximate an end of the wrap cycle. In addition, in some embodiments, the clamp includes first and second jaws, and the first jaw has at least one longitudinal groove and the second jaw includes at least one longitudinal rib that is received within the at least one longitudinal groove when the clamp is actuated to provide greater holding resistance in a first direction transverse to the axis of rotation than in a second direction parallel to the axis of rotation.
Consistent with another aspect of the invention, an apparatus for wrapping a load may include a paper-based packaging material dispenser configured to dispense a web of paper-based packaging material to the load, a rotational drive configured to generate relative rotation between the paper-based packaging material dispenser and the load about an axis of rotation during a wrap cycle, and a paper-based packaging material pressing mechanism configured to adhere a trailing end of the web of paper-based packaging material to the load on each of upstream and downstream sides relative to a corner of the load proximate an end of the wrap cycle. The paper-based packaging material pressing mechanism includes an upstream pressing member configured to press the trailing end of the web of paper-based packaging material against the upstream side of the load, and a downstream pressing member configured to press the trailing end of the web of paper-based packaging material against the downstream side of the load.
Moreover, in some embodiments, the upstream pressing member is configured to press the trailing end of the web of paper-based packaging material against the upstream side of the load while adhesive is disposed between the trailing end of the web of paper-based packaging material and the upstream side of the load, and the downstream pressing member is configured to press the trailing end of the web of paper-based packaging material against the downstream side of the load while adhesive is disposed between the trailing end of the web of paper-based packaging material and the downstream side of the load.
Some embodiments may also include an adhesive applicator configured to apply adhesive to the upstream and downstream sides of the load prior to pressing the trailing end of the web of paper-based packaging material against the upstream and downstream sides of the load. Some embodiments may further include a controller, and the controller is configured to control the apparatus to, prior to completing a last wrap around the load, actuate the adhesive applicator to apply the adhesive to first and second portions of the web of paper-based packaging material that respectively overlay the upstream and downstream sides of the load, and thereafter complete the last wrap around the load such that the trailing end of the web of paper-based packaging material overlays at least the first portion of the web of paper-based packaging material.
Some embodiments may also include an arm configured to support the adhesive applicator and controllably move the adhesive applicator into a position to apply adhesive to the web of paper-based packaging material. In some embodiments, the upstream and downstream pressing members are separately actuatable. In addition, in some embodiments, the paper-based packaging material pressing mechanism further includes a cutter configured to sever the trailing end of the web of paper-based packaging material.
In some embodiments, the paper-based packaging material pressing mechanism is configured to press the trailing end of the web of paper-based packaging material against the upstream side of the load with the upstream pressing member prior to severing the trailing end of the web of paper-based packaging material, and to press the trailing end of the web of paper-based packaging material against the downstream side of the load with the downstream pressing member after severing the trailing end of the web of paper-based packaging material. Moreover, in some embodiments, the paper-based packaging material pressing mechanism further includes an arm configured to support the upstream and downstream pressing members, the arm being movable between a first position separated from the load and a second position proximate the load. Also, in some embodiments, the paper-based packaging material pressing mechanism is configured to press the upstream pressing member against the upstream side of the load through movement of the arm, and to press the downstream pressing member against the downstream side of the load through actuation of a downstream pressing member actuator after movement of the arm to the second position.
Consistent with another aspect of the invention, an apparatus for wrapping a load may include a paper-based packaging material dispenser configured to dispense a web of paper-based packaging material to the load, a rotational drive configured to generate relative rotation between the paper-based packaging material dispenser and the load about an axis of rotation during a wrap cycle, and a paper-based packaging material roping mechanism configured to form a rope along a bottom edge of the web of paper-based packaging material. The paper-based packaging material roping mechanism includes a substantially horizontal surface, and first and second substantially vertical rollers positioned proximate the substantially horizontal surface and separated from one another by a gap, and when the bottom edge of the web of paper-based packaging material is received in the gap between the first and second substantially vertical rollers, the first and second substantially vertical rollers gather and crease the bottom edge of the web of paper-based packaging material against the substantially horizontal surface and into a rope.
In some embodiments, the first and second substantially vertical rollers are horizontally movable to track the web of paper-based packaging material during at least a portion of the relative rotation. In addition, some embodiments may also include first and second guides positioned upstream of the first and second substantially vertical rollers. Also, in some embodiments, the first and second guides define an upwardly-facing opening. Moreover, in some embodiments, the first and second guides are horizontally movable to track the web of paper-based packaging material during at least a portion of the relative rotation. Further, in some embodiments, the substantially horizontal surface is defined on a substantially horizontal roller. Also, in some embodiments, the first and second substantially vertical rollers are cone shaped.
Consistent with another aspect of the invention, a method may be provided for wrapping a load with a load wrapping apparatus that includes a paper-based packaging material dispenser configured to dispense a web of paper-based packaging material to the load and a rotational drive configured to generate relative rotation between the paper-based packaging material dispenser and the load about an axis of rotation during a wrap cycle. The method may include moving a platen downwardly along the axis of rotation to engage with a top of the load and to position a leading end of the web of paper-based packaging material within an opening of a first clamp supported on an arm that is rotatably mounted to the platen, actuating the first clamp to hold the leading end of the web of paper-based packaging material, initiating relative rotation between the paper-based packaging material and the load to wrap the web of paper-based packaging material around the load, including rotating the arm in response to tension in the web of paper-based packaging material during the relative rotation to move the clamp against a side of the load and wrap paper-based packaging material around the clamp, prior to completing a final rotation around the load, applying adhesive to first and second portions of the web of paper-based packaging material that overlay upstream and downstream sides of the load relative to a corner of the load, performing the final rotation around the load, pressing a trailing end of the web of paper-based packaging material against the upstream side of the load with an upstream pressing member to adhere the trailing end of the web of paper-based packaging material to the upstream side of the load, severing the trailing end of the web of paper-based packaging material, pressing the trailing end of the web of paper-based packaging material against the downstream side of the load with a downstream pressing member to adhere the trailing end of the web of paper-based packaging material to the downstream side of the load, and prior to completing the final rotation around the load, performing at least a portion of one rotation around the load while a bottom edge of the web of packaging material is received by a paper-based packaging material roping mechanism that includes a substantially horizontal surface and first and second substantially vertical rollers positioned proximate the substantially horizontal surface and separated from one another by a gap such that the bottom edge of the web of paper-based packaging material is received in the gap between the first and second substantially vertical rollers and the first and second substantially vertical rollers gather and crease the bottom edge of the web of paper-based packaging material against the substantially horizontal surface and into a rope.
Other embodiments may include a method of operating any of the load wrapping apparatus discussed above.
These and other advantages and features, which characterize the invention, are set forth in the claims annexed hereto and forming a further part hereof. However, for a better understanding of the invention, and of the advantages and objectives attained through its use, reference should be made to the Drawings, and to the accompanying descriptive matter, in which there is described example embodiments of the invention.
Embodiments consistent with the invention may, in some instances, incorporate a self-balancing paper-based packaging material dispenser to compensate for force imbalances across a web of paper-based packaging material during wrapping and thereby optimize wrapping of a load with a paper-based packaging material. Various mechanical and electromechanical mechanisms, disclosed in greater detail below, may be used to compensate for imbalanced forces exerted upon the opposing edges of a web of paper-based packaging material extending between a load and a paper-based packaging material dispenser during wrapping.
In addition, in some instances, handling of a paper-based packaging material at the beginning and end of a wrap cycle may be facilitated through the use of a load seeking clamp, a roping mechanism and/or a pressing mechanism that are specifically adapted for use with paper-based packaging materials, and that will be described in greater detail below.
A paper-based packaging material, in this regard, may be considered to include materials formed fully or partially from cellulous fibers and/or other fibers exhibiting similar characteristics, most notably a reduced stretchability and/or elasticity compared to polymer film-based packaging materials that have traditionally been used to wrap palletized loads. In some embodiments, a paper-based packaging material may include various materials that are substantially formed from wood fiber, and in some embodiments, a paper-based packaging material may include various materials that are substantially not plastically deformable, in contrast with many polymer films. Also, in some embodiments, paper-based packaging material may include various types of non-plastic, non-stretchable and/or non-elastic materials. Some non-limiting examples of paper-based packaging materials include kraft paper, coated paper, etc. It will also be appreciated, however, that the principles of the invention may also be useful for wrapping with polymer films and other plastic, stretchable or elastic materials in some embodiments.
Prior to a further discussion of the various techniques disclosed herein, however, a brief discussion of various types of wrapping apparatus within which the various techniques disclosed herein may be implemented is provided.
Various wrapping apparatus configurations may be used in various embodiments of the invention. For example,
A paper-based packaging material dispenser 112, including a roll carriage 114, is configured for movement along a direction 116 by a lift drive 118 which may, for example, include an electric motor. Roll carriage 114 supports a roll 120 of paper-based packaging material, which during a wrapping operation includes a web 122 extending between packaging material dispenser 112 and load 106, with the packaging material moving in a generally downstream direction towards the load. The terms “upstream” and “downstream,” as used in this application, are intended to define positions and movement relative to the direction of flow of packaging material as it moves from packaging material dispenser 112 to load 106. Movement of an object toward packaging material dispenser 112, away from load 106, and thus, against the direction of flow of packaging material, may be defined as “upstream.” Similarly, movement of an object away from packaging material dispenser 112, toward load 106, and thus, with the flow of the packaging material, may be defined as “downstream.”
Direction 116 is generally parallel to an axis about which packaging material is wrapped around load 106, e.g., axis 108, and movement of roll carriage 114, and thus web 122, along direction 116 during a wrapping operation enables packaging material to be wrapped spirally around the load, e.g., within a contiguous region between a top 124 and bottom 126 of load 106, e.g., region 128 between positions 130, 132 as illustrated in
Control of the position of roll carriage 114 by lift drive 118, as well as of the other drives in wrapping apparatus 100 such as rotational drive 110, is provided by a controller 134, which in the embodiment illustrated in
For the purposes of the invention, controller 134 may represent practically any type of computer, computer system, controller, logic controller, or other programmable electronic device, and may in some embodiments be implemented using one or more networked computers or other electronic devices, whether located locally or remotely with respect to the various drives 110, 118 of wrapping apparatus 100. Controller 134 typically includes a central processing unit including at least one microprocessor coupled to a memory, which may represent the random access memory (RAM) devices comprising the main storage of controller 134, as well as any supplemental levels of memory, e.g., cache memories, non-volatile or backup memories (e.g., programmable or flash memories), read-only memories, etc. In addition, the memory may be considered to include memory storage physically located elsewhere in controller 134, e.g., any cache memory in a processor, as well as any storage capacity used as a virtual memory, e.g., as stored on a mass storage device or on another computer or electronic device coupled to controller 134. Controller 134 may also include one or more mass storage devices, e.g., a floppy or other removable disk drive, a hard disk drive, a direct access storage device (DASD), an optical drive (e.g., a CD drive, a DVD drive, etc.), and/or a tape drive, among others. Furthermore, controller 134 may include an interface with one or more networks (e.g., a LAN, a WAN, a wireless network, and/or the Internet, among others) to permit the communication of information to the components in wrapping apparatus 100 as well as with other computers and electronic devices, e.g. computers such as a desktop computer or laptop computer, mobile devices such as a mobile phone or tablet, multi-user computers such as servers or cloud resources, etc. Controller 134 operates under the control of an operating system, kernel and/or firmware and executes or otherwise relies upon various computer software applications, components, programs, objects, modules, data structures, etc. Moreover, various applications, components, programs, objects, modules, etc. may also execute on one or more processors in another computer coupled to controller 134, e.g., in a distributed or client-server computing environment, whereby the processing required to implement the functions of a computer program may be allocated to multiple computers over a network.
In general, the routines executed to implement the embodiments of the invention, whether implemented as part of an operating system or a specific application, component, program, object, module or sequence of instructions, or even a subset thereof, will be referred to herein as “computer program code,” or simply “program code.” Program code typically comprises one or more instructions that are resident at various times in various memory and storage devices in a computer, and that, when read and executed by one or more processors in a computer, cause that computer to perform the steps necessary to execute steps or elements embodying the various aspects of the invention. Moreover, while the invention has and hereinafter will be described in the context of fully functioning controllers, computers and computer systems, those skilled in the art will appreciate that the various embodiments of the invention are capable of being distributed as a program product in a variety of forms, and that the invention applies equally regardless of the particular type of computer readable media used to actually carry out the distribution.
Such computer readable media may include computer readable storage media and communication media. Computer readable storage media is non-transitory in nature, and may include volatile and non-volatile, and removable and non-removable media implemented in any method or technology for storage of information, such as computer-readable instructions, data structures, program modules or other data. Computer readable storage media may further include RAM, ROM, erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other solid state memory technology, CD-ROM, digital versatile disks (DVD), or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and which can be accessed by controller 134. Communication media may embody computer readable instructions, data structures or other program modules. By way of example, and not limitation, communication media may include wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, RF, infrared and other wireless media. Combinations of any of the above may also be included within the scope of computer readable media.
Various program code described hereinafter may be identified based upon the application within which it is implemented in a specific embodiment of the invention. However, it should be appreciated that any particular program nomenclature that follows is used merely for convenience, and thus the invention should not be limited to use solely in any specific application identified and/or implied by such nomenclature. Furthermore, given the typically endless number of manners in which computer programs may be organized into routines, procedures, methods, modules, objects, and the like, as well as the various manners in which program functionality may be allocated among various software layers that are resident within a typical computer (e.g., operating systems, libraries, API's, applications, applets, etc.), it should be appreciated that the invention is not limited to the specific organization and allocation of program functionality described herein.
In the discussion hereinafter, the hardware and software used to control wrapping apparatus 100 is assumed to be incorporated wholly within components that are local to wrapping apparatus 100 illustrated in
Load Wrapping Apparatus with Self-Balancing Paper-Based Packaging Material Dispenser
As noted above, worldwide sensitivity to sustainability has increased interest in non-polymer alternatives such as kraft paper for wrapping loads, all of which tend to have reduced stretchability compared to polymer films. Wrapping a load with materials exhibiting limited stretchability, however, presents several unique concerns relative to polymer films. Spiral wrapping, where a packaging material web is moved in a direction parallel to the axis of rotation concurrently with rotating around the axis of rotation, can cause non-stretchable packaging materials such as paper-based packaging materials to exhibit undesirable characteristics such as puckering along one edge of the packaging material. Changes in pitch during a wrapping process have been found to create an imbalance on the forces exhibited on the opposing edges of the web of packaging material, and cause puckering on one edge of the web as it is wrapped around the load. In addition, where the girth of a load changes at different elevations, i.e., where the girth of the load proximate one edge of the packaging material web differs appreciably from that proximate to the other edge of the packaging material web, force imbalances may also occur and cause similar undesirable effects.
In particular, when the forces exerted on the opposing edges of a paper-based packaging material web are unbalanced, puckering has been found to occur on an edge of the web when the packaging material dispenser is moving in a direction parallel to the axis of rotation during wrapping. Likewise, puckering tends to occur in response to a change of girth in a load as packaging material is wrapped around the load while the packaging material dispenser is moving parallel to the axis of rotation.
Embodiments consistent with the invention, on the other hand, address these force imbalances by utilizing a self-balancing paper-based packaging material dispenser to compensate for the force imbalances and optimize wrapping with a paper-based packaging material. In various embodiments, an exit point of a packaging material dispenser, typically an exit roller, may be selectively inclined so that the forces exerted upon the opposing edges of the paper-based packaging material web may be substantially balanced, and this inclination in different embodiments may include only the component utilized as the exit point, or may include additional components in the packaging material dispenser in some embodiments, or even the entire packaging material dispenser in some embodiments.
Various mechanical or electromechanical approaches may be used in different embodiments to self-balance a paper-based packaging material dispenser through selective inclination of an exit point of a packaging material dispenser. In the embodiments discussed below, the exit point of a packaging material dispenser is implemented using an exit idle roller that is the last roller that the packaging material web contacts before exiting the packaging material dispenser and proceeding to the load, and is thus, the structure in the packaging material dispenser that defines one end of the packaging material web that extends between the load and the packaging material dispenser. It will be appreciated, however, that in other embodiments, the exit point may be implemented by other structures, e.g., a driven roller or a non-rotating bar or other surface.
In one example embodiment, the packaging material dispenser itself may be mounted on a low friction support bearing structure for rotation about a pivot axis that is substantially perpendicular to the axis of rotation used when wrapping (e.g., a generally horizontal axis in the case of a vertical axis of rotation for wrapping). In addition, the pivot axis of the packaging material dispenser may be selected to be positioned proximate a center of gravity of the packaging material dispenser (e.g., such that the mass of the packaging material dispenser above the pivot axis substantially equals that below the pivot axis), such that minimal torque is applied to the packaging material dispenser by gravity and any imbalance in forces exerted on the top and bottom edges of the packaging material web will naturally tilt the packaging material dispenser to tilt the exit idle roller and thereby substantially equalize the forces exerted on the top and bottom edges of the packaging material web.
In another example embodiment, a floating exit point, e.g., a floating exit idle roller, may be used to enable the floating exit point to substantially equalize the forces exerted on the top and bottom edges of the packaging material web. In some instances, for example, one or both ends of an exit idle roller may be movable to alter the inclination of the roller. In one example embodiment, an exit idle roller may be mounted to a packaging material dispenser to additionally rotate about a roller pivot axis that is generally perpendicular to the exit idle roller's axis of rotation such that the exit idle roller naturally tilts to substantially equalize the forces exerted on the top and bottom edges of the packaging material web. In another example embodiment, one or both ends of an exit idle roller may be movable in a linear direction that is generally perpendicular to the axis of rotation of the roller, and biased by a spring or other bias mechanism such that the end(s) of the exit idle roller move varying degrees along the linear direction based upon the force exerted by the proximate edge(s) of the packaging material web during wrapping.
In yet another example embodiment, an electromechanical approach may be used where, instead of allowing for free rotation or motion of a packaging material dispenser and/or an exit point thereof, one or more sensors may be used to sense the force imbalance between the opposing edges of the packaging material web, and the packaging material dispenser and/or the exit point thereof may be controllably rotated or moved to compensate for the sensed force imbalance.
It will also be appreciated that one or more of the above approaches may be combined in some embodiments, e.g., by applying different compensation mechanisms to the exit point and the packaging material dispenser itself. It will also be appreciated that in some instances the various approaches all effectively incline or tilt the exit point in a dynamic fashion, and generally in response to the forces exerted on the opposing edges of the web of paper-based packaging material. This is in contrast to controlling the inclination or tilt of an exit point of a packaging material in a predetermined fashion and/or in a manner that is not responsive to the forces exerted on the opposing edges of the web of paper-based packaging material.
In addition, in addition to or in lieu of the above approaches, some embodiments may form one or more longitudinal slits in a paper-based packaging material to effectively reduce the width of the packaging material web and thereby reduce overall force imbalances between the opposing edges of the overall packaging material web. As will become more apparent below, one or more longitudinal slits may be formed continuously during wrapping in some embodiments, or may be formed selectively in other embodiments, e.g., only when the packaging material dispenser is moving along the axis of rotation and/or only for portions of the packaging material web that are proximate the corners of the load.
Now turning to
While a number of different structures may be used in other embodiments, in the illustrated embodiment, support structure 154 of packaging material dispenser 150 is mounted to a dispenser support 168 through a low friction support bearing 170 (
As such, and as illustrated in
It will be appreciated that self-balancing paper-based packaging material dispenser 150 may be driven or undriven in different embodiments. As illustrated in
In addition, in some embodiments, a packaging material dispenser may include multiple drive rollers, e.g., in the case of packaging material dispensers designed for prestretching when used to dispense polymer-based packaging material. In such instances, it may be desirable to configure the packaging material dispenser (e.g., by selecting appropriate prestretch pulleys or gears), or otherwise control the packaging material dispenser, to drive the multiple drive rollers at a 1:1 ratio so that no prestretching is performed when used with paper-based packaging materials. By doing so, a packaging material dispenser designed for polymer-based packaging materials may be retrofitted for use with a paper-based packaging material with relatively minor modifications. It may also be desirable in some embodiments to drive the drive rollers using a variable frequency drive torque control such as is described in U.S. Publication No. 2020/0122866A1, which is assigned to the same assignee as the present application, and is incorporated by reference herein.
Next, as illustrated by self-balancing paper-based packaging material dispenser 200 in
As such, and as illustrated in
Next turning to
Each support 260, 262 includes a fixed mount 264, 266, and a bias mechanism 268, 270 (e.g., a spring) is coupled between each fixed mount 264, 266 and a corresponding mount 272, 274 disposed on an end of axle 254. Both ends of axle 254 are therefore allowed to slide within slots 256, 258 in response to forces exerted by the top and bottom edges of a web of paper-based packaging material extending between idle roller 252 and a load. As such, and as illustrated at 252′, any imbalance in forces exerted on the top and bottom edges of a packaging material web will naturally tilt exit idle roller 252 to substantially equalize the forces exerted on the top and bottom edges of the packaging material web. Selection of springs 268, 270 as well as the length and position of each slot 256, 268 may be based upon the amount of bias needed to allow for sufficient travel of each end of exit idle roller 252 to equalize forces at the top and bottom edges of the packaging material web, as will be appreciated by those of ordinary skill having the benefit of the instant disclosure.
It will be appreciated that in other embodiments, only one end of an exit idle roller may float. It will also be appreciated that other mechanical arrangements may be used to allow for movement of an end of an exit idle roller. It will also be appreciated that it may also be desirable to use bias mechanisms in packaging material dispensers 150, 200 to resist pivoting about axes P and R in some embodiments.
Now turning to
Rather than being freely pivotable about axis M, however, packaging material dispenser 300 is mounted to a motor 314 or other rotary actuator that is capable of controlling the rotation of packaging material dispenser 300 about axis M, e.g., under the control of a control circuit 316, which in some embodiments may be implemented at least in part in the main controller of a wrapping apparatus, and in other embodiments may be separate therefrom.
One or more sensors, e.g., load cells 318, 320 disposed at opposite ends of idle roller 312, may be used to sense the forces exerted at one or both edges of a packaging material web and provide feedback to control circuit 316 for use in controlling the rotational angle of packaging material dispenser 300 about pivot axis M.
While dedicated circuit logic may be used in some embodiments, in other embodiments program code executable by a controller may be used to drive motor 314 to balance the forces sensed by load cells 318, 320. Implementation of such program code would be well within the abilities of those of ordinary skill having the benefit of the instant disclosure.
In other embodiments, an electromechanical arrangement may be used to pivot only an exit point or other portion of a packaging material dispenser. In addition, it will be appreciated that different approaches may be combined, e.g., with a mechanically-movable exit roller such as illustrated in
Now turning to
A cutting mechanism 360, e.g., including one or more knives, may be used to form one or more longitudinal slits (e.g., longitudinal slits 362, 364) in packaging material web 356 after the packaging material web exits the packaging material dispenser. In some embodiments, cutting mechanism 360 may be mechanical in nature and operate continuously (e.g., to generate continuous slits such as illustrated by slit 362), while in other embodiments, cutting mechanism 360 may be electromechanical in nature and operate selectively, e.g., under the control of a control circuit 366, to generate selective slits such as illustrated by slit 364. Control circuit 366, for example, may selectively engage cutting mechanism 360 depending upon vertical movement of packaging material dispenser 350 along the axis of rotation for wrapping and/or only for portions of the packaging material web that are proximate the corners of the load. An innumerable number of slit variations may be used in various embodiments, so the invention is not limited to the particular variations discussed herein.
Load Wrapping Apparatus and Method for Wrapping with Paper-Based Packaging Material
Described next herein is an example embodiment of a wrapping apparatus and method for wrapping a load with paper-based packaging material. In this embodiment, a paper-based packaging material holder, a paper-based packaging material roping mechanism and a paper-based packaging material pressing mechanism, described in further detail below, may be used in addition to a self-balancing paper-based packaging material dispenser to wrap a load with paper-based packaging material. It will be appreciated, however, that any of a paper-based packaging material holder, paper-based packaging material roping mechanism, paper-based packaging material pressing mechanism, and self-balancing paper-based packaging material dispenser may be used separately or individually in other wrapping apparatus designs, so the invention is not limited to a wrapping apparatus incorporating all of the aforementioned components.
First, in block 402, and with additional reference to
Next, in block 404, and with additional reference to
With additional reference to
In the illustrated embodiment, arm 524 is supported by an arm support 526 that is mounted to platen 508, and that maintains a substantially constant rotational position about axis of rotation A relative to load 502 during wrapping. While in some embodiments arm 524 may move in whole or in part between the first and second positions through a linear movement, in the illustrated embodiment arm 524 is rotatably supported by arm support 526, e.g., to pivot about a pivot axis P that is substantially parallel to axis of rotation A (
Also in the illustrated embodiment, and with additional reference to
Clamp 516 may also be actuated by an actuator 536 that is able to open and close one or both of the jaws 528, 530 of the clamp to increase or decrease the width of opening 518 and hold or release leading end 520. In some embodiments, the entire clamp 516 may also be movable between retracted and operational positions, e.g., to move the clamp out of the way of the web 522.
Returning to
As will also become more apparent below, clamp 542 also holds a trailing end 552 of web 522 (
When carriage 538 is moved to the top of the load, clamp 516 is desirably in an unactuated state such that the opening 518 is sufficiently wide enough to receive leading end 520 of web 522, such that, proximate a start of the wrap cycle, a controller may move leading end 520 of the web 522 in the direction along the axis of rotation A while being held by clamp 542 such that the leading end of the web is received within opening 518 of clamp 516.
Then, as illustrated by block 408 of
Next, as illustrated by block 410 of
Next, as illustrated by block 414 of
Next, as illustrated by block 416 of
As noted above, roping mechanism 560 may be configured to form a rope along a bottom edge 556 of web 522, and may include a substantially horizontal surface, e.g., as defined on a horizontal roller 562, first and second substantially vertical rollers 564, 566 positioned proximate horizontal roller 562 and separated from one another by a gap 568, and a pair of guides 570, 572 that are positioned upstream of rollers 564, 566. Rollers 564, 566 and guides 570, 572 may be mounted on a support 574 that is horizontally movable (e.g., along a horizontal bearing 576) such that when web 522 is positioned between guides 570, 572 and in gap 568, support 574 and the components supported thereby will move horizontally with the web and in effect track the web during relative rotation between the load and the paper-based packaging material dispenser. Horizontal roller 562 has a sufficient width to accommodate the changes in web location, although in other embodiments a narrower roller that is supported on support 574 may alternatively be used.
Guides 570, 572 define an upward-facing opening 578 that receives web 522 when carriage 538 is at an appropriate height, and when carriage 538 is lowered to a sufficient point that bottom edge 556 is lower than horizontal roller 562, the bottom edge, within gap 568, will be gathered and creased by rollers 564, 566 against the surface of horizontal roller 562, thereby forming a rope along the bottom of web 522. The height of horizontal roller 562 is set such that when the rope is formed, the rope will be wound about pallet 558, desirably at a location where room remains on the side of the pallet for fork truck forks to be inserted.
As best illustrated in
Rollers 564, 566 in the illustrated embodiment may be cone shaped, e.g., with a portion of the rollers being tapered at one end, e.g., as shown in
Returning to
The tail treatment operation relies in part on a paper-based packaging material pressing mechanism, e.g., pressing mechanism 580 illustrated in
Prior to pressing the pressing members against the load, however, it is desirable in some embodiments to apply adhesive between the trailing end and paper-based packaging material already applied to the load, and desirably to do so for both upstream and downstream sides 582, 584, such that when the trailing end is pressed against the upstream and downstream sides of the load, the trailing end is adhered to the load by the adhesive.
As such, and returning to
Next, as illustrated by block 422 of
Next, as illustrated by block 426 of
In the illustrated embodiment, pressing of upstream pressing member 588 against the upstream side of the load is initiated simply through movement of arm 598 by actuator 602. A second downstream pressing member actuator 604 is in turn coupled to downstream pressing member 590 to separately press the downstream pressing member against the downstream side of the load once arm 598 is in the second position, and as such, upstream and downstream pressing members 588, 590 are separately actuatable despite being supported on the same arm 598. In other embodiments, both pressing members may be actuated concurrently, and in other embodiments, both pressing members may be separately and independently supported and actuated, e.g., supported on different arms.
A cutter 606 is additionally supported on arm 606 to sever trailing end 552 of web 522. As such, during block 426 of
Returning to
Once the trailing end is pressed against the downstream side of the load, the wrap cycle is complete. Moreover, at this time, dispenser clamp 542 already holds a new leading end of web 522 in preparation for wrapping a future load.
Various modifications may be made to the illustrated embodiments. For example, a separate roll support may be used in some embodiments to support large and heavy rolls of paper-based packaging material, moving along with carriage 538 to maintain a substantially constant height relative to carriage 538. In addition, rather than being rotated into operative positions, various components described herein, e.g., adhesive applicator 592 and paper-based packaging material pressing mechanism 580 may be stationary in some embodiments, or may be moved in other manners, e.g., via linear motion and/or through rotation about a horizontal axis of rotation. In addition, in some embodiments, one or more intersecting finned rollers (or other alternative device) may be mounted on carriage 538 and used to perform an initial scoring of a web to enhance the formation of “pleats” by a roping mechanism.
In addition, while the aforementioned process of
Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the present invention. Therefore, the invention lies in the claims set forth hereinafter.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2023/014511 | 3/3/2023 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63317070 | Mar 2022 | US |
