Tip of the Cap

While the materials involved have changed dramatically over the years, bottles with closures can be counted among history’s first packaging types. For any bottled product today, quality and safety naturally hinge on properly sealed and lined bottle closures. For over two decades, MMC Packaging, based in Laval, Quebec, has supplied state-of-the-art, turnkey post-molding automation equipment to leading manufacturers of container caps and specialty closures.

With over 1,000 systems in the field worldwide, MMC Packaging is renowned for its work in cap lining machines (wadding machines), assembly machines, cap slitting machines, closing machines, vision systems and other custom automation equipment.

MMC Packaging machines handle caps after the plastic injection molding or metal forming processes. For example, a typical MMC lining machine cuts and inserts lining material into newly molded caps. This liner cutting and insertion process requires the execution of a series of events in a synchronized manner.

Different MMC lining machine types are designed to suit different cap sizes, and the number of “ups” on the machine (i.e. caps produced per index) determines the throughput. The LM 270, for example, is a 2-up machine that performs at 150 cycles per minute, but processes 300 parts per minute. MMC Packaging machines are well known for accommodating easy changeovers in less than 30 minutes and certain models can run several tooling types.

Outgrowing the PLC

While continuing its mission to boost machine equipment quality, MMC Packaging found concerning limitations in the area of hardware PLCs. “The difficulties with a traditional PLC platform include limitations in processing speed, system memory, data storage and database capabilities, among other challenges,” explains Mathieu Ouellet, MMC Packaging’s VP of business and product development. “As MMC Packaging endeavored to modernize our systems, we needed more processing power and flexibility from our controller platform. This meant a change of control technology was in order.”

Ensuring perfect product quality requires top quality of the machine itself as well as the automation and controls components. “The LM-270 is the best-selling machine from MMC Packaging and we must maintain the shortest lead times possible so we started the development of our new controls platform there,” explains MMC President and owner, Philippe McNally. “This latest lining machine generation leverages advanced PC-based control technology, industrial Ethernet technology and a revolutionary user interface that provides critical production data in real-time to our clients.”

This also includes comprehensive operational and performance data from the machine so MMC clients have up-to-the-second information regarding the health and efficiency of equipment. The LM-270 cap lining machine features an intelligent console called the MMC-icon, which serves as the central information hub for machine and production data.

Today, MMC Packaging touts a range of new capabilities for troubleshooting in real-time data management via the system database. The status of all the sensors and actuators, current voltage – everything – is recorded and available for system analysis and troubleshooting purposes.

PC-Based Control

During the development of the new and improved LM-270 cap lining machine as well as the company’s new QTVision (Quality Through Vision) system and the MMC-icon solutions, MMC needed a user interface with a selection of standard programming tools. The first steps toward PC-based control actually started with research into industrial Ethernet technologies.

MMC Packaging supplies state-of-the-art, turnkey automation equipment to manufacturers of container caps and specialty closures.

“We first encountered PC-based control from Beckhoff Automation because of EtherCAT,” explains Yan Letourneau, MMC’s senior electrical designer. “I was impressed with the speed and capabilities of EtherCAT, so I started following the technology, and attended a Beckhoff seminar about EtherCAT. As another design need at the time, I sought an HMI panel capable of multi-touch functionality and found that Beckhoff also offers a range of solutions in this area so I quickly got in touch with the Beckhoff sales team in Quebec.”

As the control programming platform, MMC Packaging standardized on TwinCAT 3, which supports all IEC 61131-3 programming languages, object-oriented programming (OOP), C/C++ and provides many other optional tools to programming engineers. Another highlight in TwinCAT 3 is the possibility to reserve individual CPU cores of a multi-core processor exclusively for TwinCAT. This feature, known as “CPU Isolation,” gives the full performance of the reserved cores solely to TwinCAT.

All LM-270 automation, including conveyor control, reject functions and confirmation of rejects are handled using TwinCAT 3 now. With PC-based control, the company was also able to implement more efficient timing on the machines.

“With TwinCAT 3, manual intervention is minimized when performing timing changes on the machine,” Letourneau adds. “Using automatic timing in software, the LM 270 machine, with all its connected peripherals, can easily change speed on the fly and adapt the equipment rate to the volume and production needs of our clients.”

TwinCAT 3 NC PTP controls and synchronizes the events of indexing, cutting and inserting lining materials with registration marks. “We also use TwinCAT 3 Scope to record all the data in the process,” Letourneau explains. “The data is stored on the hard drive of a Beckhoff C6525 fanless built-in industrial PC.” In addition to recording production data, the LM-270 leverages the same C6525 IPC as the centralized control hardware along with Beckhoff CP391x multi-touch control panels for the display hardware. Beckhoff controls, a CX2040 Embedded PC, are also used on MMC’s QTVision line.

“We previously used a ‘white box’ PC with the control programmed with C++ and had four or more cameras connected to it,” Letourneau says. “That PC couldn’t keep up with the vision programs, which caused a CPU load of around 70%. After moving to the CX2040 and TwinCAT 3, we went from 70% CPU load down to 30%. With four cameras, we can inspect up to 2,400 caps per minute and process up to 9,600 images per minute using the CX2040 without causing strain on the CPU.”

With the new controls platform and interface, MMC Packaging utilizes 3D models and tutorial videos to supplement operator training and support. “The ability to run all tasks including automation, PLC, motion control and the Windows based graphical interface on a single device was a huge factor in favor of PC-based control as well,” Ouellet says. “Our 3D manual utilizes multi-touch functionality programmed using C++ or C and includes pinch gestures to zoom in/out and view valuable equipment information and learn how to best operate the machine.”

Wearing Many Caps

Control speeds in the low microsecond range are now commonplace for MMC Packaging, such as triggering cameras in the vision systems at 250 microseconds. As with any equipment manufacturer today, better machine diagnostic information improves the end customer’s ability to identify potential problems, pinpoint them and resolve them before unplanned downtime occurs. With a wider range of data logging and troubleshooting tools, MMC expects to significantly reduce their customer assistance intervention time and boost their customers’ uptime as a result. Enhanced diagnostics capabilities and remote connectivity through the PC- and EtherCAT-based control platform are the key enablers.

“TwinSAFE also demonstrates another added value from EtherCAT,” Letourneau says. “Even for safety technology, I still use standard Ethernet cables. All the safety data goes through the EtherCAT protocol and there are TwinSAFE terminals throughout the machine. A system-integrated programmable safety solution is much easier to modify in the future as our machine designs evolve.” MMC Packaging mainly uses TwinSAFE for e-stops, safety guards, integrated servo drive safety and for safety measures on VFDs.

The control console of the LM-270 from MMC Packaging leverages Beckhoff CP391x multi-touch control panels for the display hardware and a fanless C6525 Industrial PC as the centralized control hardware.

To implement the servo drive safety, MMC Packaging utilizes Beckhoff AX5000 EtherCAT servo drives equipped with AX5801 or AX5805 TwinSAFE drive option cards for safe stop functions (STO, SS1). The TwinSAFE-enabled AX5000 servo drives are paired to AM8000 series servo motors with one cable technology (OCT), which cuts the number of motor cables and connectors by 50%.

“One Cable Technology in our servo system along with the EtherCAT I/O system and TwinSAFE have been instrumental in streamlining our machine designs,” Ouellet says. “Instead of managing all control wires from the central units to all of our peripherals, we now only have to wire a single Ethernet cable, which dramatically cuts our wiring cost and saves 20 to 24 hours of installation time per setup.” It is also possible to integrate any standard Ethernet device with EtherCAT, the cables used are standard and no proprietary fieldbus cards are needed. MMC Packaging also uses EtherCAT gateway terminals that provide an easy interface to other networks and protocols when required.

High Density (HD) EtherCAT Terminals in 16 channel format also help MMC save space in electrical cabinets. “With HD Terminals, we have replaced outdated terminals that had fewer I/O points and inefficient screw-type connections,” Letourneau says. “The EtherCAT I/O terminals we use today have efficient Cage Clamp connections which enable far simpler wiring. This streamlines machine setup and results in shorter machine lead times as well. We reduced electrical cabinet space by more than 30% and the savings can be directly traced back to the EtherCAT I/O system and compact PC-based controllers like the C6525 IPCs and CX2040 Embedded PCs.”

“The first stage of the MMC Packaging controls upgrade is officially complete,” states Anthi Balafoutis, MMC’s sales and marketing coordinator. “The LM 270, MMC-icon and QTVision machines are only the first of our machine lines to be equipped with Beckhoff PC-based controls. The next step is to develop and implement this technology on all other machine lines we offer, including MMC assembly, sealing and slitting machines. We will also retrofit existing MMC machines already in the field.”

www.mmcpackaging.com
www.beckhoff.ca