Page 10 - MetalForming May 2010

SafetyUpdate Safety Catchers Secure Platens Under Suspended Load
Advanced Machine & Engineering, Rockford, IL, has begun to market safety devices called
safety catchers, manufactured by Ger- many-based Sitema GmbH & Co., a
supplier of clamping units and lin-
ear brakes. The device stops and
locks a dropping platen via a
wedge mechanism located on a
smooth rod that can be placed in
any position. It’s activated by the
weight of the dropping mass. Among
its applications: hydraulic presses.
Some presses are equipped with safety devices that operate in only one or a few positions, such as interference rods or link- age mechanisms. The upper platen must travel the full stroke even if a fraction of the stroke would be sufficient for production reasons. With such devices, total safety may not be guaranteed, say Sitema representatives. If, for example, an emergency stop or a power failure occurs in the middle of the full stroke, the latching device cannot be activated. With multiple-ratchet-posi- tion devices, it is questionable whether the ratchet will prop- erly engage and withstand the forces of the dropping mass.
Installing the safety catchers on hydraulic press- es, and other machines in which drop- ping masses are a concern, can elim- inate such dangers. The locking position functions for the entire stroke of the machine, which guarantees a safety stop at any stroke position. The full locking force is created only by the load. The unit will lock only when the safety catcher is in locking position (no hydraulic or pneumatic pressure is present) and the load is moving downward (such as when the
acting hydraulic cylinder of the press is leaking).
Advanced Machine & Engineering: 815/962-6076; www.ame.com
Hygiene-Products Manufacturer Acquires Safety Company
Kimberly-Clark Corp., Dallas, TX, a manufacturer of dis- posable wipes, washroom and skin-care products, acquired
8 METALFORMING / MAY 2010
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