Further discussion of press brakes for this memorandum is limited to general and special purpose machines. The basic difference between these machines is the way the system controls their operation. General-purpose machines are equipped with only one operator control station, while specialty machines may have multiple operator stations/auxiliary control locations. In general, general purpose brakes can be characterized by a control system that is mechanically linked to the clutch/brake mechanism or to a hydraulic control valve. Electrical or pneumatic components are rarely part of the control system. And controls can only be removed by mechanical means such as control locks or by removing the control pedal. Hydraulic Press Brake
Universal mechanical press brakes
Universal mechanical press brakes activated by significantly depressing the pedal. Which mechanically releases the brake and simultaneously releases the clutch. Thereby initiating the sliding motion. The return springs release the clutch and re-engage the brake when foot pressure released. Single stroke mechanisms not require. And anti-repeat devices are not available. A general purpose hydraulic press brake must have a single stroke capacity that will stop the ram at the top of the stroke even if the operator does not release the control.
Combination of these methods
Special purpose press brakes actuate by a servo system. Which in turn is controlled by one or more stations and operator controls. The servo system can be electric, pneumatic, hydraulic, or a combination of these methods and controls the clutch/brake mechanism to allow the piston to move. All special purpose electric press brakes must be equipped with an anti-repeat feature that limits the press to one stroke even when the shutdown control is locked. General purpose press brakes can be operated by one operator and each helper(s) must be held in place by restraints, pulls or restraints.
Some forms of auxiliary safety are ineffective and cannot be used with general purpose press brakes. Special purpose press brakes are equipped with sophisticated control systems to accommodate all forms of protection and tooling concepts. Devices include two-hand controls and multiple operator/assistant controls. A general purpose press brake can be modified to convert into a special purpose press brake. Modified press brakes can accommodate a wider range of protection concepts.
Press brakes
And are reclassified as special purpose press brakes. Due to the many different types of press brakes available and used in the industry. It is necessary to clearly define the type of machine to addressed before evaluating the hazards associated with that particular machine. Safety at the place of operation of a press brake is not simply a matter of whether or not it is guarded.
