The invention generally relates to wrapping loads with packaging material through relative rotation of loads and a packaging material dispenser, and in particular, to a control system therefor.
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 packaging material around a load. The packaging material may 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.
In many commercial applications, typical loads wrapped by a stretch wrapping machine have a substantially cuboid shape with a relatively consistent length, width and height throughout, and in many cases having a similar length and width to the supporting pallet. Generally, in these applications, loads consist of multiple layers of the same products, and a standard wrapping cycle may be optimized to handle these standard-type loads. In other applications, however, loads may deviate from this traditional configuration, and may include portions or layers, herein referred to as inboard portions, that are substantially inboard of a supporting body upon which they are disposed and to which they must be secured. In still other instances, loads may have additional specialized requirements such as corner boards to protect the corners of the load, top sheets to protect loads from the environment, etc., which often requires dedicated machinery to handle in an automated fashion. Dedicated machinery, however, is not practical for all applications, as the cost of the machinery may exceed the derived benefits, particularly for lower cost wrapping machines and/or where specialized load requirements are only infrequently encountered.
Therefore, a continuing need exists in the art for a manner of accommodating specialized load requirements in a cost effective manner.
The invention addresses these and other problems associated with the art by providing in one aspect a method, apparatus and program product that utilize wrap profiles including controlled wrap cycle interruptions to handle specialized load requirements. The wrap profiles define additional wrap parameters for use in wrapping a load such that, through selection of a particular wrap profile, both the wrap parameters suitable for wrapping a load, as well as a controlled wrap cycle interruption suitable for handling a specialized requirement for the load, may be determined by a load wrapping apparatus when wrapping the load.
Therefore, consistent with one aspect of the invention, a method is provided for controlling a load wrapping apparatus of the type configured to wrap a load on a load support with packaging material dispensed from a packaging material dispenser through relative rotation between the packaging material dispenser and the load support. The method may include receiving input data selecting a wrap profile from among a plurality of wrap profiles for the load wrapping apparatus, where each of the plurality of wrap profiles includes a plurality of wrapping parameters that control operation of the load wrapping apparatus when wrapping, and where the selected wrap profile includes a wrapping parameter among the plurality of wrapping parameters that identifies a controlled wrap cycle interruption to be performed when wrapping the load, and performing a wrap cycle using the selected wrap profile to wrap the load with packaging material, including performing the controlled wrap cycle interruption during the wrap cycle.
In some embodiments, the controlled wrap cycle interruption temporarily pauses or stops relative rotation between the packaging material dispenser and the load support prior to completion of the wrap cycle. Also, in some embodiments, the controlled wrap cycle interruption temporarily decreases a relative rotation speed between the packaging material dispenser and the load support prior to completion of the wrap cycle. Also, in some embodiments, the controlled wrap cycle interruption prematurely terminates the wrap cycle prior to completion of the wrap cycle. Further, in some embodiments, the controlled wrap cycle interruption temporarily changes a dispense rate of the packaging material dispenser prior to completion of the wrap cycle.
Further, in some embodiments, the packaging material dispenser is configured for movement between a plurality of positions along a direction generally parallel to an axis about which packaging material is wrapped around the load when the load is disposed on the load support, and where the controlled wrap cycle interruption moves the packaging material dispenser to a selected position among the plurality of positions prior to completion of the wrap cycle.
In some embodiments, performing the controlled wrap cycle interruption includes notifying an operator. In addition, in some embodiments, notifying the operator includes displaying an alert to the operator on a display of the load wrapping apparatus. In some embodiments, notifying the operator includes displaying one or more instructions to the operator to prompt the operator to perform a manual activity associated with the controlled wrap cycle interruption.
In some embodiments, the controlled wrap cycle interruption includes a top box secure operation. In some embodiments, the top box secure operation includes, upon detecting a top of the load, temporarily reducing relative rotation speed and tension in a web of packaging material for one or more relative rotations to enable an operator to manually manipulate the web to secure an article on a top layer of the load.
In addition, in some embodiments, the controlled wrap cycle interruption includes an add corner boards operation. Moreover, in some embodiments, the add corner boards operation includes positioning the packaging material dispenser at a predetermined elevation and temporarily reducing relative rotation speed for a relative rotation to enable an operator to manually insert corner boards along each of a plurality of corners of the load.
In some embodiments, the controlled wrap cycle interruption includes an add top sheet operation. In some embodiments, the add top sheet operation includes, upon detecting a top of the load, lowering the packaging material dispenser to a predetermined elevation and pausing the wrap cycle to enable an operator to manually place a top sheet over the load, and where the add top sheet operation further includes, after restarting of the wrap cycle following placement of the top sheet, performing one or more relative rotations at a reduced relative rotation speed and resuming the wrap cycle.
Moreover, in some embodiments, the controlled wrap cycle interruption includes a one way wrap operation. In some embodiments, the one way wrap operation includes, upon detecting a top of the load, stopping the wrap cycle to enable an operator to cut a web of packaging material extending between the packaging material dispenser and the load.
In some embodiments, the controlled wrap cycle interruption includes a stack and wrap operation. In addition, in some embodiments, the stack and wrap operation includes, for each of a plurality of layers of the load, detecting a top of the load, and in response to detecting the top of the load, pausing the wrap cycle to enable an operator to manually place a next layer on top of the load. In some embodiments, the stack and wrap operation includes, for each of a plurality of layers of the load, detecting a top of the load, and in response to detecting the top of the load, pausing the wrap cycle and notifying an external machine to place a next layer on top of the load.
Moreover, in some embodiments, the controlled wrap cycle interruption includes a band two loads operation. Also, in some embodiments, the load is a first load, and the band two loads operation includes moving the packaging material dispenser to a predetermined position proximate a top of the first load in response to operator input and wrapping one or more bands of packaging material around the first load and a lower portion of a second load placed on top of the first load to secure the first and second loads to one another.
Some embodiments may also include causing a plurality of wrap profile indicators to be displayed on a display, each wrap profile indicator associated with a wrap profile from among the plurality of wrap profiles, where receiving the user input selecting the wrap profile includes receiving user input selecting the wrap profile indicator associated with the selected wrap profile. In addition, in some embodiments, each of the plurality of wrap profiles further specifies a minimum number of layers of packaging material and a wrap force to be applied to the load. Also, in some embodiments, the minimum number of layers and the wrap force specified by each wrap profile are selected to meet a load containment force requirement specified by such wrap profile. In addition, in some embodiments performing the wrap cycle further includes controlling the load wrapping apparatus to wrap the load using the minimum number of layers and wrap force specified by the selected wrap profile such that the load containment force requirement specified by the selected wrap profile is met when the load is wrapped.
Further, in some embodiments, the load has first and second opposing ends defined generally along a direction generally parallel to an axis about which packaging material is wrapped around the load when the load is disposed on the load support, where the load wrapping apparatus is further configured for movement of a portion of a web of packaging material relative to the load in the direction generally parallel to the axis, and where controlling the load wrapping apparatus includes, during relative rotation between the packaging material dispenser and the load support, controlling movement of the web of packaging material in the direction generally parallel to the axis to apply at least the minimum number of layers of packaging material specified by the selected wrap profile to the load throughout a contiguous region extending between first and second positions respectively disposed proximate the first and second opposing ends of the load, and controlling a dispense rate of the packaging material dispenser based on the wrap force specified by the selected wrap profile.
Also, in some embodiments, the load wrapping apparatus is configured to perform a standard wrapping operation that wraps packaging material in a spiral manner around a load starting and ending proximate a bottom of the load, where the controlled wrap cycle interruption deviates from the standard wrapping operation, and where the method further includes receiving second input data selecting a second wrap profile from among the plurality of wrap profiles that does not identify any controlled wrap cycle interruption to be performed when wrapping the load, and performing a second wrap cycle using the second wrap profile to wrap a second load with packaging material using the standard wrapping operation.
Consistent with another aspect of the invention, a method is provided for creating a wrap profile for a load wrapping apparatus of the type configured to wrap a load on a load support with packaging material dispensed from a packaging material dispenser through relative rotation between the packaging material dispenser and the load support. The method may include receiving first input data selecting a plurality of wrapping parameters that control operation of the load wrapping apparatus when wrapping the load, receiving second input data selecting a controlled wrap cycle interruption from among a plurality of controlled wrap cycle interruptions, where each of the controlled wrap cycle interruptions is configured to accommodate a specialized load requirement, and storing the selected plurality of wrapping parameters and the selected controlled wrap cycle interruption as a wrap profile in a wrap profile database accessible by the load wrapping apparatus.
Consistent with another aspect of the invention, a load wrapping apparatus may include a packaging material dispenser configured to dispense a web of packaging material to a load, a first drive mechanism configured to generate relative rotation between the packaging material and the load about an axis of rotation, a second drive mechanism configured to control an elevation of the web of packaging material generally parallel to the axis of rotation, and a controller coupled to the first and second drive mechanisms and configured to access a selected wrap profile from among a plurality of wrap profiles stored in a wrap profile database and control the first and second drive mechanisms while wrapping the load using the selected wrap profile, where each of the plurality of wrap profiles in the wrap profile database includes a plurality of wrapping parameters that control operation of the load wrapping apparatus when wrapping, where the selected wrap profile includes a wrapping parameter among the plurality of wrapping parameters that identifies a controlled wrap cycle interruption to be performed when wrapping the load, and where the controller is configured to perform the controlled wrap cycle interruption when wrapping the load using the selected wrap profile.
Consistent with another aspect of the invention, an apparatus may include a processor, and program code configured upon execution by the processor to control a load wrapping apparatus of the type configured to wrap a load on a load support with packaging material dispensed from a packaging material dispenser through relative rotation between the packaging material dispenser and the load support by performing any of the aforementioned methods. Also, in some embodiments, the processor is in a controller of the load wrapping apparatus, and the apparatus further includes a packaging material dispenser for dispensing packaging material to the load. Further, in some embodiments, the processor is in a device external to the load wrapping apparatus. In addition, in some embodiments, the device is a mobile device, a single-user computer or a multi-user computer.
Consistent with another aspect of the invention, a program product may include a non-transitory computer readable medium, and program code stored on the non-transitory computer readable medium and configured to control a load wrapping apparatus of the type configured to wrap a load on a load support with packaging material dispensed from a packaging material dispenser through relative rotation between the packaging material dispenser and the load support, where the program code is configured to control the load wrapping apparatus by performing any of the aforementioned methods.
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 exemplary embodiments of the invention.
Embodiments consistent with the invention utilize wrap profiles with controlled wrap cycle interruptions to facilitate operator interaction with a load wrapping apparatus, particularly in connection with accommodating specialized load requirements. Prior to a discussion of the aforementioned concepts, however, a brief discussion of various types of wrapping apparatus within which the various techniques disclosed herein may be implemented is provided.
Packaging material dispenser 106 may include a pre-stretch assembly 112 configured to pre-stretch packaging material before it is applied to load 110 if pre-stretching is desired, or to dispense packaging material to load 110 without pre-stretching. Pre-stretch assembly 112 may include at least one packaging material dispensing roller, including, for example, an upstream dispensing roller 114 and a downstream dispensing roller 116. It is contemplated that pre-stretch assembly 112 may include various configurations and numbers of pre-stretch rollers, drive or driven roller and idle rollers without departing from the spirit and scope of the invention.
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 108 as it moves from packaging material dispenser 106 to load 110. Movement of an object toward packaging material dispenser 106, away from load 110, and thus, against the direction of flow of packaging material 108, may be defined as “upstream.” Similarly, movement of an object away from packaging material dispenser 106, toward load 110, and thus, with the flow of packaging material 108, may be defined as “downstream.” Also, positions relative to load 110 (or a load support surface 118) and packaging material dispenser 106 may be described relative to the direction of packaging material flow. For example, when two pre-stretch rollers are present, the pre-stretch roller closer to packaging material dispenser 106 may be characterized as the “upstream” roller and the pre-stretch roller closer to load 110 (or load support 118) and further from packaging material dispenser 106 may be characterized as the “downstream” roller.
A packaging material drive system 120, including, for example, an electric motor 122, may be used to drive dispensing rollers 114 and 116. For example, electric motor 122 may rotate downstream dispensing roller 116. Downstream dispensing roller 116 may be operatively coupled to upstream dispensing roller 114 by a chain and sprocket assembly, such that upstream dispensing roller 114 may be driven in rotation by downstream dispensing roller 116. Other connections may be used to drive upstream roller 114 or, alternatively, a separate drive (not shown) may be provided to drive upstream roller 114.
Downstream of downstream dispensing roller 116 may be provided one or more idle rollers 124, 126 that redirect the web of packaging material, with the most downstream idle roller 126 effectively providing an exit point 128 from packaging material dispenser 102, such that a portion 130 of packaging material 108 extends between exit point 128 and a contact point 132 where the packaging material engages load 110 (or alternatively contact point 132′ if load 110 is rotated in a counter-clockwise direction).
Wrapping apparatus 100 also includes a relative rotation assembly 134 configured to rotate rotating arm 104, and thus, packaging material dispenser 106 mounted thereon, relative to load 110 as load 110 is supported on load support surface 118. Relative rotation assembly 134 may include a rotational drive system 136, including, for example, an electric motor 138. It is contemplated that rotational drive system 136 and packaging material drive system 120 may run independently of one another. Thus, rotation of dispensing rollers 114 and 116 may be independent of the relative rotation of packaging material dispenser 106 relative to load 110. This independence allows a length of packaging material 108 to be dispensed per a portion of relative revolution that is neither predetermined nor constant. Rather, the length may be adjusted periodically or continuously based on changing conditions.
Wrapping apparatus 100 may further include a lift assembly 140. Lift assembly 140 may be powered by a lift drive system 142, including, for example, an electric motor 144, that may be configured to move roll carriage 102 vertically relative to load 110. Lift drive system 142 may drive roll carriage 102, and thus packaging material dispenser 106, upwards and downwards vertically on rotating arm 104 while roll carriage 102 and packaging material dispenser 106 are rotated about load 110 by rotational drive system 136, to wrap packaging material spirally about load 110.
One or more of downstream dispensing roller 116, idle roller 124 and idle roller 126 may include a corresponding sensor 146, 148, 150 to monitor rotation of the respective roller. In particular, rollers 116, 124 and/or 126, and/or packaging material 108 dispensed thereby, may be used to monitor a dispense rate of packaging material dispenser 106, e.g., by monitoring the rotational speed of rollers 116, 124 and/or 126, the number of rotations undergone by such rollers, the amount and/or speed of packaging material dispensed by such rollers, and/or one or more performance parameters indicative of the operating state of packaging material drive system 120, including, for example, a speed of packaging material drive system 120. The monitored characteristics may also provide an indication of the amount of packaging material 108 being dispensed and wrapped onto load 110. In addition, in some embodiments a sensor, e.g., sensor 148 or 150, may be used to detect a break in the packaging material.
Wrapping apparatus also includes an angle sensor 152 for determining an angular relationship between load 110 and packaging material dispenser 106 about a center of rotation 154 (through which projects an axis of rotation that is perpendicular to the view illustrated in
Additional sensors, such as a load distance sensor 156 and/or a film angle sensor 158, may also be provided on wrapping apparatus 100. Wrapping apparatus 100 may also include additional components used in connection with other aspects of a wrapping operation. For example, a clamping device 159 may be used to grip the leading end of packaging material 108 between cycles. In addition, a conveyor (not shown) may be used to convey loads to and from wrapping apparatus 100. Other components commonly used on a wrapping apparatus will be appreciated by one of ordinary skill in the art having the benefit of the instant disclosure.
An example schematic of a control system 160 for wrapping apparatus 100 is shown in
Controller 170 in the embodiment illustrated in
As noted above, sensors 146, 148, 150, 152 may be configured in a number of manners consistent with the invention. In one embodiment, for example, sensor 146 may be configured to sense rotation of downstream dispensing roller 116, and may include one or more magnetic transducers 180 mounted on downstream dispensing roller 116, and a sensing device 182 configured to generate a pulse when the one or more magnetic transducers 180 are brought into proximity of sensing device 182. Alternatively, sensor assembly 146 may include an encoder configured to monitor rotational movement, and capable of producing, for example, 360 or 720 signals per revolution of downstream dispensing roller 116 to provide an indication of the speed or other characteristic of rotation of downstream dispensing roller 116. The encoder may be mounted on a shaft of downstream dispensing roller 116, on electric motor 122, and/or any other suitable area. One example of a sensor assembly that may be used is an Encoder Products Company model 15H optical encoder. Other suitable sensors and/or encoders may be used for monitoring, such as, for example, optical encoders, magnetic encoders, electrical sensors, mechanical sensors, photodetectors, and/or motion sensors.
Likewise, for sensors 148 and 150, magnetic transducers 184, 186 and sensing devices 188, 190 may be used to monitor rotational movement, while for sensor 152, a rotary encoder may be used to determine the angular relationship between the load and packaging material dispenser. Any of the aforementioned alternative sensor configurations may be used for any of sensors 146, 148, 150, 152, 154 and 156 in other embodiments, and as noted above, one or more of such sensors may be omitted in some embodiments. Additional sensors capable of monitoring other aspects of the wrapping operation may also be coupled to controller 170 in other embodiments.
For the purposes of the invention, controller 170 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 drive systems 120, 136 and 142 of wrapping apparatus 100.
Controller 170 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 170, 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 170, e.g., any cache memory in a processor in CPU 52, 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 170. Controller 170 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 170 may include an interface 190 with one or more networks 192 (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 single-user desktop computer or laptop computer 194, mobile devices such as a mobile phone 196 or tablet 198, multi-user computers such as servers or cloud resources, etc. Controller 170 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 170, 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 170. 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
Now turning to
Packaging material dispenser 206 may include a pre-stretch assembly 212 including an upstream dispensing roller 214 and a downstream dispensing roller 216, and a packaging material drive system 220, including, for example, an electric motor 222, may be used to drive dispensing rollers 214 and 216. Downstream of downstream dispensing roller 216 may be provided one or more idle rollers 224, 226, with the most downstream idle roller 226 effectively providing an exit point 228 from packaging material dispenser 206, such that a portion 230 of packaging material 208 extends between exit point 228 and a contact point 232 where the packaging material engages load 210.
Wrapping apparatus 200 also includes a relative rotation assembly 234 configured to rotate rotating ring 204, and thus, packaging material dispenser 206 mounted thereon, relative to load 210 as load 210 is supported on load support surface 218. Relative rotation assembly 234 may include a rotational drive system 236, including, for example, an electric motor 238. Wrapping apparatus 200 may further include a lift assembly 240, which may be powered by a lift drive system 242, including, for example, an electric motor 244, that may be configured to move rotating ring 204 and roll carriage 202 vertically relative to load 210.
In addition, similar to wrapping apparatus 100, wrapping apparatus 200 may include sensors 246, 248, 250 on one or more of downstream dispensing roller 216, idle roller 224 and idle roller 226. Furthermore, an angle sensor 252 may be provided for determining an angular relationship between load 210 and packaging material dispenser 206 about a center of rotation 254 (through which projects an axis of rotation that is perpendicular to the view illustrated in
Packaging material dispenser 306 may include a pre-stretch assembly 312 including an upstream dispensing roller 314 and a downstream dispensing roller 316, and a packaging material drive system 320, including, for example, an electric motor 322, may be used to drive dispensing rollers 314 and 316, and downstream of downstream dispensing roller 316 may be provided one or more idle rollers 324, 326, with the most downstream idle roller 326 effectively providing an exit point 328 from packaging material dispenser 306, such that a portion 330 of packaging material 308 extends between exit point 328 and a contact point 332 (or alternatively contact point 332′ if load 310 is rotated in a counter-clockwise direction) where the packaging material engages load 310.
Wrapping apparatus 300 also includes a relative rotation assembly 334 configured to rotate turntable 304, and thus, load 310 supported thereon, relative to packaging material dispenser 306. Relative rotation assembly 334 may include a rotational drive system 336, including, for example, an electric motor 338. Wrapping apparatus 300 may further include a lift assembly 340, which may be powered by a lift drive system 342, including, for example, an electric motor 344, that may be configured to move dispenser support 302 and packaging material dispenser 306 vertically relative to load 310.
In addition, similar to wrapping apparatus 100, wrapping apparatus 300 may include sensors 346, 348, 350 on one or more of downstream dispensing roller 316, idle roller 324 and idle roller 326. Furthermore, an angle sensor 352 may be provided for determining an angular relationship between load 310 and packaging material dispenser 306 about a center of rotation 354, and in some embodiments, one or both of a load distance sensor 356 and a film angle sensor 358 may also be provided. Sensor 352 may be positioned proximate center of rotation 354, or alternatively, may be positioned at other locations, such as proximate the edge of turntable 304. Wrapping apparatus 300 may also include additional components used in connection with other aspects of a wrapping operation, e.g., a clamping device 359 may be used to grip the leading end of packaging material 308 between cycles.
Each of wrapping apparatus 200 of
Those skilled in the art will recognize that the example environments illustrated in
During a typical wrapping operation, a clamping device, e.g., as known in the art, is used to position a leading edge of the packaging material on the load such that when relative rotation between the load and the packaging material dispenser is initiated, the packaging material will be dispensed from the packaging material dispenser and wrapped around the load. In addition, where prestretching is used, the packaging material is stretched prior to being conveyed to the load. The dispense rate of the packaging material is controlled during the relative rotation between the load and the packaging material, and a lift assembly controls the position, e.g., the height, of the web of packaging material engaging the load so that the packaging material is wrapped in a spiral manner around the load from the base or bottom of the load to the top. Multiple layers of packaging material may be wrapped around the load over multiple passes to increase overall containment force, and once the desired amount of packaging material is dispensed, the packaging material is severed to complete the wrap.
In the illustrated embodiments, to control the overall containment force of the packaging material applied to the load, both the wrap force and the position of the web of packaging material are both controlled to provide the load with a desired overall containment force. The mechanisms by which each of these aspects of a wrapping operation are controlled are provided below.
In many wrapping applications, the rate at which packaging material is dispensed by a packaging material dispenser of a wrapping apparatus is controlled based on a desired payout percentage, which in general relates to the amount of wrap force applied to the load by the packaging material during wrapping. Further details regarding the concept of payout percentage may be found, for example, in the aforementioned U.S. Pat. No. 7,707,801, which is assigned to the same assignee as the present application, and which is incorporated by reference herein in its entirety.
In many embodiments, for example, a payout percentage may have a range of about 80% to about 120%. Decreasing the payout percentage slows the rate at which packaging material exits the packaging material dispenser compared to the relative rotation of the load such that the packaging material is pulled tighter around the load, thereby increasing wrap force, and as a consequence, the overall containment force applied to the load. In contrast, increasing the payout percentage decreases the wrap force. For the purposes of simplifying the discussion hereinafter, however, a payout percentage of 100% is initially assumed.
It will be appreciated, however, that other metrics may be used as an alternative to payout percentage to reflect the relative amount of wrap force to be applied during wrapping, so the invention is not so limited. In particular, to simplify the discussion, the term “wrap force” will be used herein to generically refer to any metric or parameter in a wrapping apparatus that may be used to control how tight the packaging material is pulled around a load at a given instant. Wrap force, as such, may be based on the amount of tension induced in a web of packaging material extending between the packaging material dispenser and the load, which in some embodiments may be measured and controlled directly, e.g., through the use of an electronic load cell coupled to a roller over which the packaging material passes, a spring-loaded dancer interconnected with a sensor, a torque control device, or any other suitable sensor capable of measuring force or tension in a web of packaging material.
On the other hand, because the amount of tension that is induced in a web of packaging material is fundamentally based upon the relationship between the feed rate of the packaging material and the rate of relative rotation of the load (i.e., the demand rate of the load), wrap force may also refer to various metrics or parameters related to the rate at which the packaging material is dispensed by a packaging material dispenser.
Thus, a payout percentage, which relates the rate at which the packaging material is dispensed by the packaging material dispenser to the rate at which the load is rotated relative to the packaging material dispenser, may be a suitable wrap force parameter in some embodiments. Alternatively, a dispense rate, e.g., in terms of the absolute or relative linear rate at which packaging material exits the packaging material dispenser, or the absolute or relative rotational rate at which an idle or driven roller in the packaging material dispenser or otherwise engaging the packaging material rotates, may also be a suitable wrap force parameter in some embodiments.
To control wrap force in a wrapping apparatus, a number of different control methodologies may be used. For example, in some embodiments of the invention, the effective circumference of a load may be used to dynamically control the rate at which packaging material is dispensed to a load when wrapping the load with packaging material during relative rotation established between the load and a packaging material dispenser, and thus control the wrap force applied to the load by the packaging material, e.g., as is disclosed in U.S. Pub. No. 2014/0116007, which is assigned to the same assignee as the present application, and which is incorporated by reference herein in its entirety. The effective circumference of a load throughout relative rotation may be indicative of an effective consumption rate of the load, which may in turn be indicative of the amount of packaging material being “consumed” by the load as the load rotates relative to the packaging dispenser. In particular, effective consumption rate, as used herein, generally refers to a rate at which packaging material would need to be dispensed by the packaging material dispenser in order to substantially match the tangential velocity of a tangent circle that is substantially centered at the center of rotation of the load and substantially tangent to a line substantially extending between a first point proximate to where the packaging material exits the dispenser and a second point proximate to where the packaging material engages the load. This line is generally coincident with the web of packaging material between where the packaging material exits the dispenser and where the packaging material engages the load.
The manner in which the dimensions (i.e., circumference, diameter and/or radius) of the tangent circle may be calculated or otherwise determined may vary in different embodiments. In some embodiments, for example, a sensed film angle may be used to determine various dimensions of a tangent circle, e.g., effective radius and/or effective circumference. Alternatively or in addition to the use of sensed film angle, various additional inputs may be used to determine dimensions of a tangent circle. For example, a film speed sensor, such as an optical or magnetic encoder on an idle roller, may be used to determine the speed of the packaging material as the packaging material exits the packaging material dispenser. In addition, a laser or other distance sensor may be used to determine a load distance (i.e., the distance between the surface of the load at a particular rotational position and a reference point about the periphery of the load). Furthermore, the dimensions of the load, e.g., length, width and/or offset, may either be input manually by a user, may be received from a database or other electronic data source, or may be sensed or measured.
Other manners of directly or indirectly controlling wrap force may be used in other embodiments without departing from the spirit and scope of the invention, including various techniques and variations disclosed in the aforementioned materials incorporated by reference herein, as well as other wrap speed or wrap force-based control packaging material dispense techniques known in the art.
As noted above, during a wrapping operation, the position of the web of packaging material is typically controlled to wrap the load in a spiral manner.
A packaging material dispenser 610, including a roll carriage 612, is configured for movement along a direction 614 by a lift mechanism 616. Roll carriage 612 supports a roll 618 of packaging material, which during a wrapping operation includes a web 620 extending between packaging material dispenser 610 and load 606.
Direction 614 is generally parallel to an axis about which packaging material is wrapped around load 606, e.g., axis 608, and movement of roll carriage 612, and thus web 620, along direction 614 during a wrapping operation enables packaging material to be wrapped spirally around the load.
In some embodiments, it may be desirable to provide at least a minimum number of layers of packaging material within a contiguous region on a load. For example, load 606 includes opposing ends along axis 608, e.g., a top 622 and bottom 624 for a load wrapped about a vertically oriented axis 608, and it may be desirable to wrap packaging material between two positions 626 and 628 defined along direction 614 and respectively proximate top 622 and bottom 624. Positions 626, 628 define a region 630 therebetween that, in the illustrated embodiments, is provided with at least a minimum number of layers of packaging material throughout.
The position of roll carriage 612 may be sensed using a sensing device (not shown in
Control of the position of roll carriage 612, as well as of the other drive systems in wrapping apparatus 600, is provided by a controller 632, the details of which are discussed in further detail below.
Conventionally, stretch wrapping machines have controlled the manner in which packaging material is wrapped around a load by offering control input for the number of bottom wraps placed at the base of a load, the number of top wraps placed at the top of the load, and the speed of the roll carriage in the up and down traverse to manage overlaps of the spiral wrapped film. In some designs, these controls have been enhanced by controlling the overlap inches during the up and down travel taking into consideration the relative speed of rotation and roll carriage speed.
However, it has been found that conventional control inputs often do not provide optimal performance, as such control inputs often do not evenly distribute the containment forces on all areas of a load, and often leave some areas with insufficient containment force. Often, this is due to the relatively complexity of the control inputs and the need for experienced operators. Particularly with less experienced operators, operators react to excessive film breaks by reducing wrap force and inadvertently lowering cumulative containment forces below desirable levels.
Some embodiments consistent with the invention, on the other hand, utilize a containment force-based wrap control to simplify control over wrap parameters and facilitate even distribution of containment force applied to a load. In particular, in some embodiments of the invention, an operator specifies a load containment force requirement that is used, in combination with one or more attributes of the packaging material being used to wrap the load, to control the dispensing of packaging material to the load.
A load containment force requirement, for example, may include a minimum overall containment force to be applied over all concerned areas of a load (e.g., all areas over which packaging material is wrapped around the load). In some embodiments, a load containment force requirement may also include different minimum overall containment forces for different areas of a load, a desired range of containment forces for some or all areas of a load, a maximum containment force for some or all areas of a load.
A packaging material attribute may include, for example, an incremental containment force/revolution (ICF) attribute, which is indicative of the amount of containment force added to a load in a single revolution of packaging material around the load. The ICF attribute may be related to a wrap force or payout percentage, such that, for example, the ICF attribute is defined as a function of the wrap force or payout percentage at which the packaging material is being applied. In some embodiments, the ICF attribute may be linearly related to payout percentage, and include an incremental containment force at 100% payout percentage along with a slope that enables the incremental containment force to be calculated for any payout percentage. Alternatively, the ICF attribute may be defined with a more complex function, e.g., s-curve, interpolation, piecewise linear, exponential, multi-order polynomial, logarithmic, moving average, power, or other regression or curve fitting techniques. It will be appreciated that other attributes associated with the tensile strength of the packaging material may be used in the alternative.
Other packaging material attributes may include attributes associated with the thickness and/or weight of the packaging material, e.g., specified in terms of weight per unit length, such as weight in ounces per 1000 inches. Still other packaging material attributes may include a wrap force limit attribute, indicating, for example, a maximum wrap force or range of wrap forces with which to use the packaging material (e.g., a minimum payout percentage), a width attribute indicating the width (e.g., in inches) of the packaging material, and/or additional identifying attributes of a packaging material (e.g., manufacturer, model, composition, coloring, etc.), among others.
A load containment force requirement and a packaging material attribute may be used in a wrap control consistent with the invention to determine one or both of a wrap force to be used when wrapping a load with packaging material and a number of layers of packaging material to be applied to the load to meet the load containment force requirement. The wrap force and number of layers may be represented respectively by wrap force and layer parameters. The wrap force parameter may specify, for example, the desired wrap force to be applied to the load, e.g., in terms of payout percentage, or in terms of a dispense rate or force.
The layer parameter may specify, for example, a minimum number of layers of packaging material to be dispensed throughout a contiguous region of a load. In this regard, a contiguous region of a load may refer to a region of a load between two different relative elevations along an axis of relative rotation and throughout which it is desirable to apply packaging material. In some embodiments, the contiguous region may be considered to include all sides of a load, while in other embodiments, the contiguous region may refer to only a single side or subset of sides, or even to a line extending along a side of a load between different elevations.
With regard to the concept of a minimum number of layers of packaging material, a minimum number of layers of three, for example, means that at any point on the load within a contiguous region wrapped with packaging material, at least three overlapping layers of packaging material will overlay that point. Put differently, the number of layers may also be considered to represent a combined thickness of packaging material applied to the load. As such, in some embodiments, the layer parameter may be specified in terms of a minimum combined thickness of packaging material to be dispensed through a contiguous region of a load. In some embodiments, the combined thickness may be represented in terms of layers, while in other embodiments, the combined thickness may be represented in terms of the actual packaging material thickness represented by the combined layers of packaging material applied to the load. Nonetheless, for the purposes of this disclosure, the terms “number of layers” and “combined thickness” may be used interchangeably.
In addition, while a layer parameter in the embodiments hereinafter is based upon a minimum value throughout a contiguous region of a load, in other embodiments, a layer parameter may be based on an average, median or other calculation related to the combined thickness of packaging material throughout at least a portion of the contiguous region.
Moreover, it will be appreciated that a layer parameter may specify other control parameters that, when utilized, provide the desired minimum number of layers or combined thickness, e.g., an amount of overlap between successive revolutions, a carriage or elevator speed, a number of up and/or down passes of the carriage or elevator, a number of relative revolutions, etc. For example, in some embodiments, carriage speed and the number of up and/or down passes may be used as layer parameters to provide a desired minimum number of layers or combined thickness of packaging material during a wrapping operation. In some other embodiments, however, no separate determination of minimum number of layers or combined thickness may be performed, and layer parameters based on overlap, carriage speed and/or number of passes may be used.
A layer parameter may also specify different number of layers for different portions of a load, and may include, for example, additional layers proximate the top and/or bottom of a load. Other layer parameters may include banding parameters (e.g., where multiple pallets are stacked together in one load).
Now turning to
Each wrap profile 658 stores a plurality of wrap parameters, including, for example, a containment force parameter 662, a wrap force (or payout percentage) parameter 664, and a layer parameter 666. In addition, each wrap profile 658 may include a name parameter providing a name or other identifier for the profile. The name parameter may identify, for example, a type of load (e.g., a light stable load type, a moderate stable load type, a moderate unstable load type or a heavy unstable load type), or may include any other suitable identifier for a load (e.g., “20 oz bottles”, “Acme widgets”, etc.).
In addition, a wrap profile may include additional wrap parameters, collectively illustrated as advanced parameters 670, that may be used to specify additional instructions for wrapping a load. Additional parameters may include, for example, an overwrap parameter identifying the amount of overwrap on top of a load, a top parameter specifying an additional number of layers to be applied at the top of the load, a bottom parameter specifying additional number of layers to be applied at the bottom of the load, a pallet payout parameter specifying the payout percentage to be used to wrap a pallet supporting the load, a top wrap first parameter specifying whether to apply top wraps before bottom wraps, a variable load parameter specifying that loads are the same size from top to bottom, a variable layer parameter specifying that loads are not the same size from top to bottom, one or more rotation speed parameters (e.g., one rotation speed parameter specifying a rotational speed prior to a first top wrap and another rotation speed parameter specifying a rotational speed after the first top wrap), a band parameter specifying any additional layers to be applied at a band position, a band position parameter specifying a position of the band from the down limit, a load lift parameter specifying whether to raise the load with a load lift, a short parameter specifying a height to wrap for short loads (e.g., for loads that are shorter than a height sensor), etc.
In addition, in some embodiments the advanced parameters 670 may also include selection of a particular controlled wrap cycle interruption for use in customizing a wrap cycle to accommodate a specialized load requirement, as will be discussed in greater detail below.
A packaging material profile 660 may include a number of packaging material-related attributes and/or parameters, including, for example, an incremental containment force/revolution attribute 672 (which may be represented, for example, by a slope attribute and a force attribute at a specified wrap force), a weight attribute 674, a wrap force limit attribute 676, and a width attribute 678. In addition, a packaging material profile may include additional information such as manufacturer and/or model attributes 680, as well as a name attribute 682 that may be used to identify the profile. Other attributes, such as cost or price attributes, roll length attributes, prestretch attributes, or other attributes characterizing the packaging material, may also be included.
Each profile manager 654, 656 supports the selection and management of profiles in response to user input, e.g., from an operator of the wrapping apparatus. For example, each profile manager may receive user input 684, 686 to create a new profile, as well as user input 688, 690 to select a previously-created profile. Additional user input, e.g., to modify or delete a profile, duplicate a profile, etc. may also be supported. Furthermore, it will be appreciated that user input may be received in a number of manners consistent with the invention, e.g., via a touchscreen, via hard buttons, via a keyboard, via a graphical user interface, via a text user interface, via a computer or controller coupled to the wrapping apparatus over a wired or wireless network, etc.
In addition, wrap and packaging material profiles may be stored in a database or other suitable storage, and may be created using control system 650, imported from an external system, exported to an external system, retrieved from a storage device, etc. In some instances, for example, packaging material profiles may be provided by packaging material manufacturers or distributors, or by a repository of packaging material profiles, which may be local or remote to the wrapping apparatus. Alternatively, packaging material profiles may be generated via testing, e.g., as disclosed in U.S. Pub. No. 2012/0102886, which is assigned to the same assignee as the present application, and which is incorporated by reference herein in its entirety.
A load wrapping operation using control system 650 may be initiated, for example, upon selection of a wrap profile 658 and a packaging material profile 660, and results in initiation of a wrapping operation through control of a packaging material drive system 692, rotational drive system 694, and lift drive system 696.
Furthermore, wrap profile manager 654 includes functionality for automatically calculating one or more parameters in a wrap profile based upon a selected packaging material profile and/or one or more other wrap profile parameters. For example, wrap profile manager 654 may be configured to calculate a layer parameter and/or a wrap force parameter for a wrap profile based upon the load containment force requirement for the wrap profile and the packaging material attributes in a selected packaging material profile. In addition, in response to modification of a wrap profile parameter and/or selection of a different packaging material profile, wrap profile manager 654 may automatically update one or more wrap profile parameters.
In one embodiment, for example, selection of a different packaging material profile may result in updating of a layer and/or wrap force parameter for a selected wrap profile. In another embodiment, selection of a different wrap force parameter may result in updating of a layer parameter, and vice versa.
As one example, in response to unacceptable increases in film breaks, film quality issues, or mechanical issues such as film clamps or prestretch roller slippage, an operator may reduce wrap force (i.e., increase payout percentage), and functionality in the wrap control system may automatically increase the layer parameter to maintain the overall load containment force requirement for the wrap profile.
Further details regarding the configuration, modification and use of wrap profiles for use in some embodiments may be found, for example, in U.S. Pub. No. 2014/0223864, which is assigned to the same assignee as the present application, and which is incorporated by reference herein in its entirety. It will be appreciated, however, that other manners of creating, modifying and/or using wrap profiles may be used in other embodiments, so the invention is not limited to the particular operations disclosed herein and in the patents and publications incorporated by reference herein.
Moreover, it will be appreciated that while the wrap profiles discussed in connection with control system 650 are used in connection with containment force-based wrapping, where a minimum number of layers and a wrap force are defined to wrap a load to meet a load containment force requirement, in other embodiments, wrap profiles may be used in connection with other types of stretch wrapping technologies. In some embodiments, for example, wrap profiles may be used in connection with tension-based wrapping or demand-based wrapping, and may define a payout percentage or wrap tension to be used when wrapping. In such instances, a control system may be configured to maintain a substantially constant tension in a web of packaging material when wrapping a load, or alternatively, a dispense rate that is proportional to a sensed demand of the load (e.g., using an idle roller downstream of a packaging material dispenser). Further, in some embodiments a wrap profile may define a carriage speed or amount of overlap between successive layers of packaging material, rather than a minimum number of layers. Wrap profiles may in general be implemented in connection with practically any type of stretch wrapping technology, and thus, the invention is not limited to the particular stretch wrapping technologies discussed herein.
Furthermore, in some embodiments, separate wrap and packaging material profiles may not be used, and instead, one or more packaging material parameters may be incorporated into each wrap profile, thereby restricting wrap profiles to particular types of packaging material defined by the wrap profiles themselves. In still other embodiments, packaging material parameters may be stored independent of any profile.
Additional modifications will be apparent to those of ordinary skill having the benefit of the instant disclosure. Therefore, the invention is not limited to the particular embodiments discussed herein.
As noted above, many types of wrapping operations are standard wrapping operations that wrap packaging material about a generally homogeneous, non-compressible load with a generally cuboid shape. Other loads, however, may have specialized load requirements that may not be fulfilled by standard wrapping operations. As an example, particularly in warehouses and distribution centers, pallets may be individually loaded with unique combinations of goods for delivery to specific locations, resulting in loads that have irregular shapes, and in some instances, may have incomplete top layers, where as little as a single article or box sits on top of the load. In such situations, a standard wrapping operation may not sufficiently wrap around the single article or box, and creating a risk that the article or box could separate from the load during shipping.
As another example, some loads may be relatively delicate and prone to damage during shipping, particularly along the corners, thereby requiring the installation of protective corner boards on the corners of the load. Some loads likewise may be exposed to environmental conditions such as rain, snow, humidity, etc., and it may be desirable to cover the top of the load with protective material.
It may also be desirable for some loads to only wrap in one direction (e.g., from bottom to top), rather than to wrap in both directions. In addition, for some loads, it may be desirable to build loads and wrap loads iteratively, e.g., by stacking each layer of a load individually and wrapping that layer prior to stacking the next layer of the load. Further, it may be desirable to secure multiple loads together, e.g., by stacking one palletized load on top of another palletized load, and then wrapping packaging material around both loads to secure the loads together.
In some instances, particularly on many automatic-type wrapping machines, dedicated machinery may be utilized to handle some of these types of specialized load requirements. In other instances, however, particularly on many semi-automatic-type wrapping machines, dedicated machinery may not be feasible and/or cost-effective, and manual operator involvement may be needed.
In various embodiments of the invention, controlled wrap cycle interruptions are supported in wrap profiles to modify standard wrapping operations to handle various types of specialized load requirements. As such, a wrap profile for a load may be created and/or stored in a wrap profile database, and may define one or more controlled wrap cycle interruptions such that when a wrap cycle is executed using the wrap profile, the controlled wrap cycle interruption(s) will be executed by a wrapping machine during the wrap cycle.
A controlled wrap cycle interruption, in this regard, may refer to one or more interruptions to a standard wrapping operation that cause deviation from the standard sequence of wrapping packaging material in a spiral manner around a load, generally starting and ending proximate the bottom of the load. A controlled wrap cycle interruption may also be associated in some embodiments with one or more manual operator activities to be performed during the wrapping operation, and in some embodiments, a controlled wrap cycle interruption may also be associated with one or more operator prompts that alert, and in some instances, provide guidance and/or instructions to an operator to facilitate performance of one or more manual operator activities. Controlled wrap cycle interruptions may also receive timely user input in some instances such that operator control of a wrapping machine may be prompted at appropriate times in a wrap cycle to customize a controlled wrap cycle interruption for a particular load (e.g., to move a roll carriage to an appropriate height on a load, to select a next step in a multi-step operation, etc.). Such input may be via a touch screen or other graphical or textual interface in some embodiments, while in some embodiments other types of input devices may be used for some types of inputs, e.g., the use of a joystick, knob, buttons, mouse, slider, etc. to move a carriage to a desired elevation.
Controlled wrap cycle interruptions may include various operations performed prior to completion of a wrap cycle, such as temporarily pausing or stopping a wrap cycle (e.g., by pausing or stopping relative rotation between the packaging material dispenser and a load support), temporarily changing (e.g., decreasing and/or increasing) a relative rotation speed between a packaging material dispenser and a load support, prematurely terminating a wrap cycle, temporarily changing (e.g., reducing and/or increasing) a dispense rate of a packaging material dispenser, moving the packaging material dispenser to a predetermined position or elevation (e.g., by raising or lowering a roll carriage), etc.
By including controlled wrap cycle interruptions in a wrap profile, a number of potential benefits may be realized. For example, particularly since wrap profiles may be created and stored for later use, an operator may not be required to recall which loads, if any, have specialized load requirements, what those specialized load requirements are, and/or what manual activities may be required to accommodate those specialized load requirements. Thus, by including a wrap cycle interruption in a wrap profile, the specialized load requirements may be accommodated without the operator who is wrapping a load having to remember that the load has such requirements, or to specifically control a wrapping machine to accommodate such requirements (e.g., by manually stopping the wrapping machine to perform various manual operator activities). In addition, greater repeatability and consistency generally may be achieved from load to load through the inclusion of controlled wrap cycle interruptions. Moreover, in some instances, where an operator is unfamiliar with a wrapping machine or how to accommodate a specialized load requirement, the operator may be prompted and/or guided by a wrapping machine to do so. Furthermore, by supporting multiple types of controlled wrap cycle interruptions, a wrapping machine may be capable of supporting a wide variety of stretch wrapping needs for an organization, as a wrapping machine may be capable of handling a wider variety of loads.
Now turning to
First, in block 702, a home screen displayed and an operator selects an option to create a new wrap profile.
Returning to
Returning again to
Returning yet again to
Once again returning to
Next, as shown in block 712 of
Next, as shown in block 714 of
Next, as shown in block 716 of
Next, as shown in block 718 of
Returning again to
Determination of wrap force and number of layers may also be performed in any of the manners discussed above or in the aforementioned references, based in part on the load containment force requirement and the ICF determined for the current packaging material. For example, it may be desirable to associate a default number of layers for a given load stability type and adjust wrap force to meet the desired containment force requirement using the determined ICF. Limits (e.g., maximum allowable wrap force) may be checked once a wrap force is calculated, and one or more layers may be added or removed as is desired to obtain an acceptable wrap force.
In addition, in some embodiments, each load stability type may have a default number of layers and wrap force, as well as a default packaging material thickness that, when combined with the default number of layers and wrap force, is anticipated to meet a load containment force requirement for loads of that load stability type. Then, the layers/wrap force may be adjusted for the actual thickness of the packaging material that the wrap profile is being set up for, e.g., by adjusting wrap force first, and modifying the default layers only when no acceptable wrap force can be established for that containment force requirement and packaging material thickness.
In addition, in some embodiments, each containment force range selected in block 710 may be associated with a different load stability type and used to set a range of containment forces, and then, based upon load height (block 704), load shape (block 706) and pallet fit (block 708), a specific containment force requirement and associated wrap force and minimum number of layers may be determined, as taller loads may have a higher containment force requirement than shorter loads due to their relatively lower stability, and as loads with different sized layers and/or that are inboard of a pallet may be at greater risk of film breaks due to their irregular shapes and may have limits on wrap force, necessitating additional layers but at a reduced wrap force in order to meet a load containment force requirement.
Returning yet again to
Next, as illustrated by block 728 of
In addition, in block 728 a wrapping operation is performed using the wrap profile, including performing any controlled wrap cycle interruption specified by the wrap profile, and routine 700 is complete.
As noted above, various operations may be utilized as controlled wrap cycle interruptions in various embodiments, and different combinations of such interruptions may be supported in different embodiments.
Once block 924 determines it is time to add the corner boards, control passes to block 926 to optionally notify the operator, and optionally to provide guidance to the operator on how to add the corner boards. Block 928 then raises the roll carriage or packaging material dispenser a predetermined amount (e.g., about 15 inches) to position the dispenser at a predetermined elevation and holds it at that elevation for one revolution. In addition, the relative rotation speed is reduced for that revolution to give additional time for the operator to manually insert a corner board as each corner revolves past the operator. After the revolution, control passes to block 930 to increase the relative rotation speed and complete the wrap cycle according to the wrap profile.
In some embodiments, once the packaging material is cut an operator may touch a control on the touch-sensitive display to return the packaging material dispenser to a home position proximate the load support for the start of the next wrap cycle. In other embodiments, however, wrap cycles may alternate between bottom to top and top to bottom wrap cycles, whereby an operator may simply attach the packaging material to the next load at the completion of a wrap cycle and start the next wrap cycle, with wrapping occurring in an opposite direction from the prior wrap cycle.
It will be appreciated that a stack and wrap operation may also be used in connection with external machines, e.g., palletizers or robots, to place each layer on the pallet rather than by an operator. Thus, the notification in block 982 may in some instances be a control signal communicated to the external machine to cause the external machine to place another layer of articles on the pallet. In addition, it will also be appreciated that in some embodiments, stabilizers may also be added in connection with a stack and wrap operation.
Other controlled wrap cycle interventions may be implemented in other embodiments to accommodate other specialized load requirements, as will be appreciated by those of ordinary skill having the benefit of the instant disclosure. In addition, various additional specialized wrapping operations may also be supported in some embodiments, e.g., band two loads operations where the elevation of the band is controlled via user input of a height of the bottom load, a short load operation where an input height of the load is used to control the wrap operation instead of sensing the height with a height sensor, a dust cover operation where a load is quickly wrapped with a low wrap force to provide a dust cover to a load not needing any supplemental containment, or a produce operation where a roping mechanism is used to reduce the width of a web of packaging material (by roping the top and/or bottom edges) and the narrowed width of the web and an input layer height is used to apply bands across the layer boundaries between layers of the load, among others.
Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the present invention. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/IB2018/057341 | 9/21/2018 | WO | 00 |
Number | Date | Country | |
---|---|---|---|
62562096 | Sep 2017 | US |