Upgrades for Thermoformer Controls

For many thermoforming operations, the most important recent advances have come in electronics, and specifically in controls. Advances in control technology give thermoformers in a position to purchase new machinery a significant competitive edge. However, thermoformers with a perfectly sound basic production system are often understandably reluctant to purchase a replacement system to gain the advantages of state-of-the-art electronics alone. Now, there are alternatives.

Thermoformers can install control system upgrades. Control upgrades solve many control problems that typically limit thermoformer performance, including inconsistent chain indexing, hard to use and understand operator controls and old, outdated oven controls. A variety of solutions to problems caused by outdated controls are available. It is useful, however, to take a close look at an upgrade option. A typical thermoformer upgrade, such as provided by Machinery Control Systems (MCS), offers thermoformers an “off-the-shelf” Allen-Bradley SLC500 PLC based control system upgrade. It includes a modern control enclosure containing what is needed to make a thermoformer work consistently. All hard-wired push buttons are replaced with a 15" operator-friendly touch-screen. The touch-screen interfaces to the SLC500 to control the following: form press, pumps, oven control, timers, recipe saving/loading, machine and motion diagnostics. The touch-screen also interfaces to the MCS motion controller, which controls chain index length and speed. An operator simply enters the index length and speed from the touch-screen and the system sees that it is maintained. Ten easily accessed screen selections are located at the top of the Windows™ screen. From left to right the screens are Timer Setup, Buttons, Oven Heat, Press Cycle Graphic, Load, Save, Op LS, Far LS, Motion Tuning, Password, and Exit. The operator may leave the machine in MANUAL mode or let the system take full control of the cycle by using an AUTO mode. The screen also displays which doors are open and closed.

The Timer Control Screen allows an operator to adjust all sequence timers, which include: forming and trim press, vacuum, stacker, air blow off and more during the forming cycle. For each time period there is a delay to close and a delay to open. This allows staggered press closing and opening.

The Oven Control Screen displays the oven heaters as they are in the oven. Pressing each zone touch-cell allows setting easy oven zone temperature set point. The actual temperature of each zone is also displayed. The operator may individually turn each oven zone on/off. All oven temperature zones are PID controlled.

According to David Anzano, MCS president, the thermoformer control upgrade was originally custom designed for a specific customer. 

“We found the upgrade significantly improved thermoformer performance under a variety of conditions. This fully developed, thoroughly tested, production-proven upgrade can benefit a wide range of thermoformers. Installation is easy and a thermoformer can realize benefits immediately.”

Founded in 1987, Machinery Control Systems Inc. is a systems integrator that designs and installs process control systems, including electrical engineering, instrumentation and software development. MCS offers customers turnkey solutions supported by single source responsibility. Experienced with distributive Control Systems using both PLC and PC based systems; MCS can integrate an entire range of industrial control hardware and software, including field devices such as sensors, motors, valves, etc. MCS’s creative approach to process control systems includes use of up-to-the-minute technology. MCS systems reduce expenses and increase efficiency and are backed by a commitment to long-term support.