Since the advent of general purpose motion control 25 years ago, packaging machinery has always been a primary target on the radar screen for suppliers. Packaging is filled with line-oriented machines and heavy demands for higher speeds, torques, accuracies and the dynamic performance that are an ideal fit for servos. Advanced motion software for electronic gearing, camming and registration control are fundamental requirements for packaging machines which thrive on tightly coordinated, multi-axis motion control.
Today, the need for highly flexible operation and a continuing drive to maximize throughput, provide the biggest challenges and opportunities. New motion products are more powerful and compact and new system architectures offer technology solutions for a wide range of packaging machinery applications.
Here is a series of application vignettes exploring how automation and motion control solutions are still evolving to provide better solutions for packaging machinery.
Automation Package Cuts Tubular Bag Commissioning in Half
A new integrated automation package for bag-making machines from Siemens reduces commissioning time by up to 50 percent. The SIMOTION® Easy Set Baggers & Wrappers package combines automation hardware with a software library containing customizable modules for standardized tasks. The package offers features for vertical bag makers (intermittent and continuous) and flow-wrap machines that can be extended with advanced options.
Hardware components include drive-based SIMOTION D motion control, in-feed and power sections of the SINAMICS® drive series, digital and analog I/O, HMI and power supply. The motion control permits the PLC and motion control to be programmed in a single device.
The software library provides an operating mode manager developed in accordance with the OMAC (Open Modular Architecture Controls) standardized packaging machine automation guidelines and has a data interface to connect higher-level systems that use the PackML specification.
Open software modules automate components of a tubular bag machine including transverse sealer, foil feed with printing mark correction or slip compensation, pre-feed and temperature control with auto-tuning.
The library simplifies machine variant automation and, if additional cross-sealing equipment is needed, operators can change by selecting the appropriate software module from the library.
Individual component control including homing, jogging and setting offset positions are performed in manual mode. Commissioning and machine setup are performed in manual mode as well and are supported by diagnostic information on the operating device.
In automatic operation, machine motion components are coordinated. Automatic operation is required when the motions for dosing, foil feed and transverse sealer must be matched. Motion overlay may be used to optimize the cycle count of the machine. A “jogging in synchronous grouping” function visually checks component coordination for non-stop machine operation.
UVA Packaging, a manufacturer of vertical and horizontal form fill-and-seal machines, uses the Easy Set package. On new continuous motion vertical bag makers, the package allows machines to be completed in half the planned time. Instead of implementing basic functions, engineers can concentrate on applying their special know-how to the process itself and improving the performance of the machines.
Ethernet-based Motion Simplifies Ultra-fast Linear Labeling
A switch to Ethernet Powerlink motion control components is simplifying electrical system building for Harland Machine Systems, a manufacturer of ultra-high-speed linear labeling machines.
“Ethernet Powerlink technology has helped us to make our electrical system both simpler and more modular,” says Tec Wright, product development manager at Harland. “It means that we can build systems for clients more quickly.
“The high-speed Ethernet network has so much bandwidth that we now have much more flexibility to customize labeling machines, and incorporate additional features that are invariably required at commissioning stage and after installation,” he says.
The new system has substantially reduced the hardware and wiring on a new variant of Harland's Mercury labeling system, a machine that applies front and back pressure-sensitive labels at up to 275 products per min.
Harland's linear machines are built from two main elements. The core machine has six servo motor axes for feeding, positioning and stabilizing products on a conveyor; plus a modular labeling head with a pair of stepper motor axes for applying labels to both the front and back of a bottle. Four labeling heads with auto-change facility for continuous throughput allows reel changeovers to take place without stopping the line.
The speed of the Mercury machine, combined with its programmability for different product types, places real-time demands on the motion control hardware. The main controller and the labeling heads each require several high-speed inputs for product registration. The main controller must also dynamically change cam motion profiles to enable quick changeover between product types.
This complexity, plus the need for multiple high-speed inputs, means the previous Mercury machine needed seven discrete motion controllers for a typical dual-head configuration. A new system configuration using Baldor's Ethernet Powerlink controller reduces this to three. The technology also reduces system building complexity for Harland. All of the servo drives and I/O on the main machine are interconnected by a daisy-chained Ethernet cable, saving wiring and space as well as eliminating dozens of assembly operations.
Secure PC-Based Control for Package Printing Market
A leading printing and labeling systems manufacturer developed a new PC-based control system to capture emerging “promotions” package printing market in just three months.
“Starting from zero prior experience with industrial PCs to finished product was a fairly seamless process,” says Damon Schingeck, technical manager at Imaje North America. “The integration of the Imaje coding and protocols into the PC-based system was straightforward.”
The project yielded the new podium-style system now called the Imaje ProControl-I™ that is adaptable to a range of packages including boxes, bottles and other plastic containers and pouches. The system supports multiple printers running simultaneously and the Imaje printers utilize continuous ink jet printing. This method electrostatically charges droplets of ink and then deflects the ink to be thrown on the packages. The print head never directly touches the product.
For the controls, Imaje selected a Beckhoff CP6502 Built-in Panel PC that provides both the hardware HMI and controller in a single unit. The Panel PC runs TwinCAT PLC software as the control platform.
This software features IEC 61131-3 and has a powerful 32-bit development environment for programs with code size and data regions that far exceed the capacities of conventional PLCs. TwinCAT PLC integrates four multi-tasking PLCs, each with four tasks in each PLC run-time system. Development and run-time systems are handled on one PC or via remote programming over TCP/IP.
The ProControl-I system handles packages moving through conveyor systems. Once packages are detected by a photo eye and encoder, the system downloads a specific code from a secure database and uses the Imaje printers to mark each product. The system can download and assign prints for up to 22 products per sec. Using features for “record cancellation after downloading” and print verification monitoring, these promotion messages are non-repeatable and the system is designed to be tamper-proof and error-free.
Consistently Flexible Android Palletizing Robot
A new type of cost-effective handling unit for mobile and flexible palletizing/de-palletizing operations provides a unique solution for end-of-line packaging, pick-and-place or palletizing applications. This new system, developed by Emkon Systemtechnik Projektmanagement GmbH, uses a scalable automation solution from Bosch Rexroth for robotic and handling tasks.
The PZ 1-K Android Series Palletizing Unit is unique because it is designed as a completely self-contained, turnkey module and comes mounted on rollers to serve as a versatile palletizing unit. The unit stacks individual products, fed from one or more conveyor systems and packs these singly or grouped in up to one to six pallet spaces. A standard vacuum gripper takes the individual products and stacks these according to a specified layout. It allows for different palletizing layouts and the introduction of slipsheets.
The Android is driven by a total of six Bosch Rexroth IndraDrive-controlled servo axes, four of which are for layered palletization and two for slipsheet handling. An IndraMotion MLC controller-based motion logic platform utilized in Emkon's Android Handling Unit offers intermediate functionality when operating with up to 16 servo axes.
The system solution offers a very fast controller which processes up to 1,000 statements in the PLC in just 60 sec and combines logic with motion control on one hardware unit. It uses IEC 61131-3 and PLCopen with specialized technology function blocks for linear six-axis interpolations, pick-and-place and palletizing applications.
In this application, the process program is generated using Emkon's offline palletizing system. A handling module from Bosch Rexroth interprets the command syntax from the offline palletizing system and converts this into specified axis movements. Operation is currently configured for four main axes plus two manual axes and fulfils a requirement for simple scaling.
Robotic Top Loader Uses Latest Pick-and-Place Technology
A robotic top-loading case packer from Sabel Engineering features a fast and reliable no-tool changeover system, a servo-driven infeed and case indexing system and utilizes the Pack ML standard packaging library.
The most critical aspect of the Model TL-10 application is precise staging of the bags for the loading process. This was accomplished by using three conveyors driven by B&R Automation ACOPOS servo drives. A random feed, in-feed conveyor transports the product toward the loading station and guarantees adequate spacing between individual items. A second product-positioning conveyor indexes the bags forward and forms groups of four. A third loading position conveyor advances the group of four to the pick station where the products are loaded into cases or bags with the robotic arm. The three conveyors perform different tasks but are always synchronized.
Another critical process is the case erecting and transport system. The system uses a servo-driven, walking beam mechanism to present the cases properly at the bag loading station. B&R servo drives combine with Bosch Rexroth actuators to provide smooth and accurate positioning of the case for loading. Flat cases are dispensed from the magazine, erected and moved into the loading position after folding the bottom flaps. Once the case is fully loaded, it is discharged and moves to the tape sealer station.
The software features of the machine are programmed using B&R's Automation Studio. Additionally, the software has been developed using the standardized Pack ML packaging library. Pack ML's goal is to provide guidelines for line types, machine state models and “tag” naming conventions for communications between packaging machines. A key initiative is to bring the benefits of ISA S88 batch manufacturing standards to packaging and create a better interface from one machine to the next, independent of the machinery manufacturer.
Adabot™ lets packagers add a robot
The R700 Adabot™ robotic case packer from Fallas Automation tracks and picks products on-the-fly and creates a system where plug-and-play robot cells can be readily added to increase productivity. The robot picks products at high speed and also tracks products to increase the overall speed of the system. Robotic case packers can be expanded by adding up to four robot cells to easily reconfigure a case packing line for higher throughputs.
The new system uses open architecture PacDrive™ automation controller from ELAU, which provides for the expansion of robot cells by plugging new robot modules into the PacDrive controller. A robotic software library provides kinematic software which simplified development of the application software.
While interfacing to a vision system is an option, a standard Adabot synchronizes with the in-feed belt through an encoder, a solution that allows the system software to provide accurate control of the robot arm. Without shifting the case or collating the product, the robot places the product anywhere inside the case. This flexibility allows an Adabot to perform A, B and U pack patterns, or any combination, through a simple recipe change at the HMI.
The system implements an elegant mechatronic design and doesn't utilize indexing systems to move, rotate and accumulate product. The design doesn't use lug belts, belt junctions or require handling of the product between the upstream wrapper and the robot. This mechanical streamlining is crucial because at high speeds, lug belt motions were not smooth enough for proper product handling. Case staging is controlled by a Schneider Electric PLC.
The modular, reusable nature of the robotic software library gives engineers an ability to readily change robot arm dimensions and move profiles, belt height and picking distances without additional programming. Adding robotic cells takes less than one min to determine the number of robots. Each robot is a task in the programming environment and the task is simply added or removed from the PacDrive controller's program. Variables are input that configure the robot for proper operation.
Integrated Architecture Helps Reduce Design Time
A leading U.S. manufacturer of case packing equipment, Combi Packaging Systems, has reduced engineering and programming time by approximately 10 to 30 percent using direct tag access.
Combi offers a range of case packing machines including drop packers, pick-and-place units and horizontal loaders, along with a case erector system within its case packing lines. But meeting the diverse needs of customers also requires Combi to have access to a wide range of scalable machine controls. Combi selected the Allen-Bradley® CompactLogix™ programmable automation controller (PAC) as the primary system for all machines, mainly for the familiarity customers already had with the controller platform.
One of the main benefits in moving to this approach was the ability to define machine code tags once in the RSLogix™ 5000 programming software and reuse of the database of code an unlimited number of times.
“In the past, programming PLC tags on our machinery was very complicated and required a lot of duplicated work as additional controllers and other device tags were imported,” says Brian Boltz, an electrical engineer for Combi. “But now, the tags are held in the controller and we can reference them anywhere in the system, which has significantly reduced our development time.”
This direct tag access was the main enabler behind the development of custom troubleshooting and diagnostic “state screen” functionality. The state screen system tracks the sequence of machine events and allows maintenance personnel to monitor segments on a PanelView terminal in real time to easily identify and diagnose any problems.
Combi also standardized on an intelligent motor control solution to decrease motor connectivity time and for implementing coordinated motion capabilities. Coordinated motion helped Combi increase the speed and throughput of its pick-and-place machinery, which helped end users cut the average cycle in half. Engineers seamlessly connect variable frequency drives, servo drives and Allen-Bradley MP-Series and TL-Series servo motors which maximizes throughput, extends the life of machine mechanics and frame assembly and enhances motor diagnostics and monitoring.