Safety still pressing for press brakes

The leading trend in press brake safety is to protect the operator without sacrificing speed or hampering operators' ability to work productively, according to press brake and safety equipment manufacturers.

If you want to learn more, please visit our website HAVEN.

This objective is being met through advancements in tooling technology, such as lighter, segmented or sectionalized tools that enhance maneuverability; safety features that prevent unsecured tools from falling; and adaptable tooling designs that minimize the need for frequent tool changes. Furthermore, innovations such as light curtains, camera and vision-based sensors, automation, robotics, and robust mechanical guards at the sides and rear contribute to this safety goal.

Light Safekeeping

Honeywell Wintriss introduces the LazerSafe' LZS-003-HS safeguarding system for hydraulic press brakes which is engineered to ensure operator safety while facilitating intricate bends.

LazerSafe employs two flat bands of 40-mm-wide laser light to oversee the zone beneath the punch, as explained by Ashok Bhide, Honeywell Wintriss product manager. It is capable of detecting objects as small as 4 mm, while maintaining tolerance against vibrations. The configuration of the laser beams, along with the positioning of the transmitter and receiver mounted on the press's ram, allows operators considerable working space, remaining safely within 20 mm of the punch.

LazerSafe features selective muting of front and rear beam sections, eliminating the need for program adjustments. This muting allows the center section of the laser to focus on monitoring the punch, enabling operators to bend box shapes without triggering alarms.

By muting the rear section of the lasers, the backgauge can be excluded from being seen as an obstruction during tasks that require short bends. According to Bhide, these enhancements enhance throughput while ensuring operator safety.

Vision-based Safeguards

Another protective alternative for press brake safety includes vision-based safety systems. The SICK V features a camera sensor installed on the upper ram of the press brake, ensuring safety throughout the downward ram movement (see Figure 1). This system establishes a safety volume underneath the punch that is actively monitored for intrusions. In the event of an intrusion, it sends a signal to halt the ram's downward motion immediately. The system leverages existing linear scales for calculating critical machine information, like the upper beam's position, velocity, and stopping distance.

"Parts are becoming increasingly intricate while cycle times are shortening," stated Steve Aamodt, SICK machine tools market manager. "It is essential that press brake safety equipment does not impede productivity or throughput while still safeguarding the operator.

Safety Starts With Tooling

A significant facet of press brake safety revolves around the tooling system, including how tools are loaded, clamped, and secured onto the machine, according to Gunter Glocker, president of Wila USA.

Utilizing precision, segmented tooling equipped with a safety pin system along with self-seating hydraulic clamping systems enhances operator safety significantly, Glocker explains (see Figure 2).

"The traditional American planer-made tooling, typically 10-12 feet long, is cumbersome and often necessitates assistance from multiple operators for loading and unloading," Glocker said.

Segmented tools are now offered in lengths not exceeding 36 inches, some measuring as little as 1 inch. This segmentation effectively lessens any individual tool's weight, allowing a single operator to manage the tools independently, as per Glocker.

Many of these tools incorporate a safety pin to prevent any risk of detachment from the ram or clamping system. Additionally, hydraulic systems perform clamping, seating, and alignment automatically for both punches and dies.

"This boosts operator safety as it eliminates the need for manual tool realignment or bringing down the ram for seating," he stated.

Wila has expanded its ram and bed clamping systems along with tooling featuring safety pins and self-seating functions to accommodate American-style precision tooling, Glocker mentioned.

Wilson Tool's sectionalized tooling enhances safety during loading and unloading and allows for single-operator setups on press brakes, according to Pat Campbell, the company’s press brake tooling division manager (see Figure 3).

Designed with safety tangs, punches are prevented from detaching from the upper beam even without clamping, significantly mitigating the risk of injuries during press brake setups and teardowns, Campbell noted.

Lighter tools feature push-buttons to retract safety tangs for easier vertical loading and unloading. In contrast, larger, heavier punches come with solid safety tangs that necessitate removing the tool by sliding it out from the end for safety in handling due to their weight.

Wilson's staged tooling reduces the requirement for punch and die changes, which minimizes the potential for mishaps, Campbell stated.

Additionally, they have recently introduced the PowerExpress, a hydraulic upper beam clamping and self-seating mechanism (see Figure 4). This system, comprising 2-foot-long sections, can be set up by a single press brake operator in under an hour, Campbell explained.

"We are also developing a modular lower die-holding unit to complement this system," he added.

All Finnish-Power brakes come standard with a SICK light curtain integrated, said Mike Stock, Finn-Power's bending product manager. Setup for this light curtain is CNC programmable and secured with password protection. "Integrating the light curtain with the brake actually boosts productivity," Stock noted.

Moreover, most brakes rated at 220 tons or lighter are now electric-powered, granting complete control of the ram at all times. "It is impossible for the ram to descend inadvertently without power due to robust safety springs," Stock affirmed.

According to Jonathan Chomicz, a sales engineer at TRUMPF Inc., the current state of safety technology neither restricts machine speed or productivity nor confines operators to specified "secure zones" in front of the brakes.

"TRUMPF has successfully merged our safety system's operation with the machine's functionalities, providing a safe and user-friendly experience for even those without extensive bending experience," Chomicz noted.

Want more information on Hydraulic Press Brake with Safety Features? Feel free to contact us.

Casey Schlachter, press brake manager for Bystronic Inc., commented that the key is establishing a reliable system that maintains production speed. Their new laser light guard system, identified as AKAS, incorporates two to three laser lights centered around the upper punch tip. This setup permits fingers to be as close as 1 in. from the pinch point without risking safety.

All Bystronic press brakes also come with standard gates at the side and rear that will halt both the ram and the backgauge if opened, Schlachter remarked.

The pressure referencing technology within Bystronic's software monitors bending pressure overloads, which may appear when a material that's too thick is placed over the V die by measuring the sheet thickness during the bending pinching phase.

COMEQ offers optional safety upgrades on its machines, including side and rear guards and an option between light curtains or laser guarding systems catering to specific customer requirements, as per president Stephen Lazinsky.

"With one of the press brakes we supply, the safety enhancement package contains redundancy across essential electrical and hydraulic components. This ensures that should any critical component fail, a backup will be available," added Lazinsky.

Robotics and Automation

Manufacturers such as Bystronic, Wila, Warcom SPA, and Amada have developed robotic press brake systems (see Figure 5), some of which can operate without any human intervention.

"Currently, robots are increasingly utilized with press brakes to manage the sheet parts at the machine," Glocker remarked. "However, most instances still require an operator to alter the tooling setups when switching from bending one part to another."

At EuroBlech, Wila introduced an innovative robotic gripper system capable of changing press brake tooling independently of an operator's presence, greatly enhancing press brake safety and productivity, Glocker mentioned. This groundbreaking robotic gripper system is set to be launched in North America this year.