Counting on your counter ejector

For the past three decades, the Langston^® Saturn Flexo Folder Gluer has set the standard for productivity and reliability in the production of corrugated boxes. The Saturn’s time-proven design, along with quality components and workmanship, has not only helped the Saturn earn its place as the “workhorse” converting machine among box makers, but also has positioned itself in today’s marketplace as a machine that can be rebuilt.

One of the major design features of the Saturn that has contributed to its acceptance and longevity in the industry is the counter ejector. The box industry requires a Flexo Folder Gluer to maintain production consistency, provide accurate bundle counts and be able to recover from jams quickly. The Saturn’s top-loading counter ejector design addresses these requirements. Pneumatic and hydraulic devices control the motion of the mechanical components that cycle to produce the finished bundles with 100-percent-accurate counts. Moreover, the working configuration of the backstop and elevator enable the operator to easily reach and remove any jams that may occur and restart production with minimal downtime. These features have served the industry well, but SUN offers enhancements that will improve Saturn performance.

Many box plants are running fewer converting machines, at higher average speeds to meet production requirements. At the same time, changes in paper quality and safety regulations, are making it more difficult for older counter ejectors to maintain the pace. Suggested improvements to the original Saturn counter ejectors include upgrades that would reduce vibrations at high speeds; a backstop design that would not mark or damage the leading edges of boxes entering the hopper; improved safety gates; and powered bundle exit conveyors that would better protect operators during jam removal. The basic principles of operation of the counter ejector are still sound, but some parts of the pneumatic and hydraulic system are obsolete and should be replaced with more modern devices.

Understanding and applying these upgrades to existing Saturn counter ejectors will increase average running speeds, improve the life of all the moving mechanical parts, eliminate edge damage to boxes at high speeds and provide a safer working environment for operators as they continue to run their Saturns as the workhorses of their plants.

Have you ever lost it?

We’ve all lost it at one time or another, and our customers notice it immediately. It’s expensive and hurts our reputation when we lose it — registration, that is. Not having control over registration in our print stations causes wasted product and devastates our production efficiency.

But what is commonly responsible for loss of registration? If we could look through the guard plates of our machines while they are running, what would we see going wrong? Common sense tells us that the “register” assembly would be responsible, and this is true. Possibly the motor brake is slipping. But is that it? Not at all. We frequently see a large amount of play in the register gears and with the connection to the print cylinder journal. Harmonic Drive reducers and Ringfeder connections solve these issues, and have other benefits as well. Let’s look a little deeper:

Although some causes for wandering rotational register are found inside the register or “compensator” assembly, often it is a poor connection between its inner hub and the print cylinder journal end. Pounding, reciprocating forces, generated by the feed and die-cutting sections send shock loads through the gear train, while the print cylinders want to continue rotating at a constant speed. The connection between the inner hub and journal end must be strong enough to take this load. OEM registers originally used a keyed connection, then later a splined connection. Over time, the forces beat these connections loose, allowing the print cylinder to move independently from the gear train ever so slightly. When this movement translates to the surface of the print plate, it becomes a significant amount of movement, or lost registration. The solution is to use a locking element, such as a Ringfeder, that squeezes inward to grab the journal and outward to grab the hub simultaneously. This type of connection is very reliable and is easy to release and retighten during repairs.

Inside the register assembly, there are typically worm gear sets that provide a compact, high-ratio reduction, allowing the small register motor to adjust the position of the heavy print cylinder. These bronze worm gear sets need regular attention. They wear and need their backlash tightened semiannually, at a minimum. The only way to avoid this expensive maintenance is to replace the worm gear set with a different type of reduction; the harmonic drive.

Harmonic drive reducers are capable of very high reductions and fit in compact spaces. They have essentially zero backlash. If sized correctly and mated with other zero backlash components, such as couplings, you can expect exceptional registration performance. Also, when coupled with a servomotor, very small incremental adjustments can be made to correct registration from a touch screen. The servo will park itself at the set location and “fight” any movement, eliminating a conventional brake and its maintenance.

Sun Automation Group offers a Digital Register with harmonic drive, servo control, Ringfedered hub connection and digital readout. Tight registration is achieved and maintained with no adjustments or additional lubrication requirements!

Langston Finishing Upgrades
Learn more about how enhancements to the Langston Saturn Flexo Folder Gluer will help make this industry workhorse better than ever.

To view past newsletters, click here.

All trademarks are the property of their respective owners.