Page 35 - MetalForming June 2015

advances in brake-stopping capability and control elec- tronics, such as the safety PLCs, that enable the ram to stop immediately when the zone is breached. In addition, advances in light curtains and refinement of methods and guidelines for their use also have improved safety while enabling efficient production of certain parts. In fact, light curtains may be the best option for a setup that creates a pinch point at a relatively long distance from the ram.
Manufacturers also are mindful of dangers posed by CNC backgauge systems, and have taken steps to address injury potential from these moving parts.
“A common solution includes a slow-approach routine in the backgauge movement,” says Bailey. “This software-driv- en parameter sets a specific safe distance from the lower tool inside the press. When a backgauge approaches to within this safe distance, its speed is reduced. This allows the operator extra time to react to the gauges and reduces likelihood of a severe injury.”
Another software-driven safety measure for CNC press brakes offers the ability to delay transition of the backgauges from one bending step to the next, or even to require oper- ators to actively confirm that they want to change steps. This helps protect operators from sudden movement of the gauges.
While manufacturers more and more include advanced safety mechanisms and controls on newly built press brakes,
retrofits remain viable alternatives as long as the brakes have the stopping and other control capabilities to take advantage of them.
Also pushing safety forward, organizations such as the Precision Metalforming Association manage committees that address press-brake safety issues and solutions, and ANSI standards undergo periodic review to update safety standards.
Automated Systems Offer Added Protection
Beyond these efforts, human safety can be improved by removing human operation. Obviously, unattended pro- duction impacts worker safety, an important attribute of automated press-brake and other panel-bending equip- ment. Panel benders provide efficient unattended production in applications where the product is shorter or thinner, or requires lower bends, according to Salvagnini officials. Anoth- er option is an automatic press-brake bending cell.
A step in the automation direction are bending aids or sheet followers.
“These specially designed lifts attach to the front of the press brake to lift and lower the part during the forming process,” Bailey explains. “This reduces working strain on the operator and, depending on the part shape, may allow an operator to stand aside and merely monitor the bending process.” MF
Power / Speed / Value Since 1937
JIER Stamping Presses
J21 One Point
J25 Two Point
J35 Front Support
J23 Inclinable
JIER North America, www.jier-na.com, Plymouth, MI USA, 734-404-6683 JIER Machine-Tool Group, www.jiermt.com, Jinan, China, 86-531-81616654
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