Packaging machines: Safeguarding operators

The Safeguard Detector Core protects operators from being injured if they reach in to refill an empty or nearly-empty magazine while a machine is still running. The packaging material in the conveyor magazine of a packaging machine acts as a physical guard during operation. If there is sufficient material in the magazine, then reaching into the mechanism while the machine is running is prevented.

Explains Dr. Martin Kidman, SICK UK safety specialist: “A machine operator is protected from being injured as long as the magazine contains material, for example flat carton blanks. That protection is gone as soon as the magazine is empty. The operating mechanism of the packaging machine is left exposed and poses a serious risk of injury."

Warning

Dr. Kidman continues: “There is a risk that operators may look to avoid stopping the machine, because of the consequent downtime and loss of work flow, and reach into the empty mechanism whilst easily defeating any safety system, if one even exists. With the SICK Safeguard Detector, a warning alarm is triggered when the minimum material fill level is reached and the machine shuts off automatically when the magazine is critically low or empty.

“The Safeguard Detector solution means there’s no need for elaborate extensions to the magazine, safety cages or complicated sensor arrangements which can be easily defeated. EN 415-7 for packaging machines advocates maintaining a minimum distance to the aperture in a machine guard by building a tunnel.

“As well as being expensive, these are not flexible when different sheet sizes are required, they can obstruct workspace access which could be a safety problem on their own and if the material is big enough it could be possible to crawl into the machine.”

SICK combined its expertise in sensing and safety technologies to create the Safeguard Detector as all-in-one packaged solution. By combining photoelectric sensors and the SICK Flexi Soft, quick-fit certified protection is provided for any printing, packaging and carton machinery with flat sheet feeding. 

Controlled by a SICK Flexi Soft safety controller, the Safeguard Detector is simple to set up or reconfigure.  The solution is TUV certified to provide immediate protection to SIL2 (EN 62061) and PLd (EN ISO 13849) and therefore reduces the need for a separate safety assessment, saving time, paperwork and costs. 

Easy to fit

The SICK Safeguard Detector is easy to fit into existing machinery and just as simple for machine developers to incorporate into new designs, offering a more cost-effective and flexible option than cumbersome and costly mechanical protection. 

Two SICK MultiPulse, MultiTask photoelectric sensors are mounted on the machine to monitor the amount of material in the magazine.  The sensors’ compact and rugged housing means they can be fitted into a small space and their excellent background and foreground suppression guards against the possibility of false signals. 

The Safeguard Detector will detect sheets and cartons with a very wide range of colours and can easily accommodate material changes. With a detection range of between 30 and 100mm, the system is suitable for a wide range of packaging machines.

An added benefit is that SICK Flexi Soft controller on the Safeguard Detector can be used for additional automation and safety functions such as door monitoring or for connecting electro-sensitive protective equipment (ESPE’S) such as safety light curtains or safety laser scanners.