How to Safely Retrofit a Woodworking Machine

To ensure that plant and machinery are always state of the art, retrofits have become increasingly established in the woodworking industry.

Safety defects that generally arise after many years of use, such as the lack of adequate safeguards, lead to a loss of machine safety. There are several immediate benefits a retrofit can bring: in addition to the updated safety technology, significant investment costs can be saved, because a new investment would cost considerably more. A retrofit will also increase the machine’s availability, as it will again be running smoothly and efficiently.  Pilz provides support in this area with tailor-made retrofit solutions.

For example, double-end tenoners – machines that process two sides of the work piece simultaneously. To increase their precision and availability, the first step is to determine whether the retrofit and increased availability need to be regarded as a significant change.

The width adjustment of these machines is critical: the implementation has to ensure that work piece transportation is safely guaranteed at all times, but that no hazards can arise for operating personnel as the adjustments are made.

The solution can be to use a safety light barrier, PSENopt, or the PSENslock / PSENsgate safety gate systems, both from Pilz. PSENopt provides protection where operator intervention is required as part of each cycle, such as insertion work, or the infeed and outfeed of material. PSENslock / PSENsgate, on the other hand, are integrated safety gate systems and cover functions such as safe monitoring, safe guard locking and control elements, including additional functions such as E-STOP and escape release, all in one unit. All components – whether mechanical or electronic - are integrated within one safety gate system.

Following the retrofit, operators now have the option in “Setup” mode to monitor the width adjustment process in the danger zone, via enable mode. Also, all the individual processing cabins are now secured in such a way that manual setup in “Setup” mode is possible at any time without risk. This gives the operator or tool setter the flexibility he or she needs for the task. “Set up” mode thus incorporates additional measures such as “Enable mode” and “Safely reduced speed”.

Keeping it Safe: Pilz Keeps an Eye on Robots

This year Ford kicked it up a notch at the North American International Auto Show (NAIAS). The exhibit was 48 percent larger than last year with 24 interactive displays, including; Active Park Assist Technology, the Control Blade Challenge and touch-screen digital displays. With all of the excitement in the booth, the highlight of the show was the EcoBoost Engine display. The center of attention, ABB robots “Eco” and “Boost” showed off the components of Ford’s new engine technology. EcoBoost can deliver up to 20 percent better fuel economy, 15 percent lower CO2 emissions, and improved driving performance when compared to larger displacement engines. The two robots from Cleveland Stamping Plant #1 took on lives of their own while interacting with the audience and product specialists. How was visitor safety ensured? Pilz Automation Safety L.P. provided the display with SafetyEYE™, nicknamed “eyes in the sky” to ensure nothing entered the area over the cell. The robot control ran with an ATI tool changer end effector safety monitored by PSS 3000 to pick up parts and engines to present them to the audience. The Pilz PSS3000 was connected to the I/O proximity switches which sensed the part position to provide safe handling of the parts. The Pilz PLC was utilized as the main controller for both safe and standard functions controlling and ensuring all safety device functions. PITmode and PSENslock from Pilz were integrated into the PSS3000 to provide access control to the cell doors. PITmode was utilized as a multifunction HMI for switching between manual and automatic modes, resetting errors, starting up robots and request to enter and lock/unlock the gate. The PITmode is an operating mode selector switch which provides two functions in one unit, the selection of operating mode and authorization control for machine access. The PITmode was the result of a joint effort with Ford Powertrain Engineers and Pilz Development. “In the real world of a plant SafetyEYE™ could have eliminated hard guarding, in this case the glass fencing. ABB’s Safe Motion technology in conjunction with SafetyEYE™ provides a comprehensive robot cell that eliminates the use of standard guarding. This is really a great partnership for all parties involved,” said Rick Pryce, business development manager for Pilz Automation Safety L.P.

For more information about Pilz Automation Safety L.P. or any of the products used in the display visit www.pilz.us. 

The innovative PSENslock series

The innovative PSENslock series, from Pilz Automation Safety L.P. the German manufacturer of safe automation components and systems, takes safety to a new level. It operates magnetically, not mechanically, as do the more traditional systems. "The PSENslock non-contact magnetic interlocking gate switch is an outstanding alternative to traditional mechanical gate switches," said Sales Engineer Ben Harper. "It's safer because it combines secure safety gate monitoring and a non-contact magnetic interlock within the same unit. And because it's mechanically non-wearing, PSENslock has a longer service life."

PSENslock has an electro-magnetic holding force of either 500 N or 1000 N to prevent the unintentional opening of swing gates and sliding gates. Its proven transponder technology is manipulation proof because the switch and actuator are totally different items. This provides an additional measure of safety. Existing mechanical technology, on the other hand, requires the use of a keyed actuator. Consequently, it's possible that this "key" could be damaged, suggesting the door is closed, creating a potentially unsafe condition. Ideal for use in rugged industrial environments, PSENslock is easy to install. With its combination of safe position monitoring and process guard locking, it's suitable for mounting onto standard 45mm profiles around the machine.

PSENslock can be used on flap gates and safety gates and is extremely tolerant to gate misalignment. With bright, double-sided LED diagnostics on both sides; it can be mounted left or right handed. An M12 plug connection allows for simple assembly. "It's really quite an achievement," Harper added. "In addition to the longer life cycle, ease of installation, higher tolerance to alignment, and strong holding force, the PSENslock has the option to include a fully coded switch which is more difficult to defeat and can be wired in series while maintaining the high safety categories that many applications demand."

PSENslock is designed for applications up to SIL3 in accordance with EN/IEC 62061, Category 4 in accordance with EN 954-1 and protection type IP67. In terms of a complete solution, PSENslock can be connected to all Pilz evaluation devices.

Pilz manufacturers a line of safety equipment used in plants. These sensors, relays and other components can be applied as individual pieces or group components to machines throughout many industries where man and manufacturing equipment are utilized together, including automotive, robotics, packaging, amusement, and wind power. The company also provides a wide array of safety consulting services.