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 Mechanical-Friction Clutch

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This is one of the most common press brakes for metal fabrication. These clutches use a part revolution mechanical-friction clutch, usually operated by a mechanical foot pedal or treadle.

Mechanical-friction clutches are widely used because they give the operator control of the machine  stroke by inching and slipping the clutch. This allows the operator to drop the slide to the workpiece and stop, adjust, or align the workpiece, then complete the stroke to bend the part.

This press also allows the operator to slip the clutch or inch through the bottom of the stroke to avoid a quick whip-up action of the material.
Press Brake with Mechanical-Friction Clutch
Mechanical-friction clutch press brake

Operator Involvement

The operator is responsible for handling the stock and operating the machine stroke through use of a foot pedal. When a foot pedal is used to begin the sequence, other safety devices must be used to keep the operators hands out of the danger zone.

 
Point of Operation
Potential Hazards:
  • A hand or other body part near the point of operation during cycling can result in injury.
  • Material can be sharp, slippery, or difficult to grasp.
Solutions:

 
Unguarded Mechanical-Friction Clutch
Unguarded press brake

  Safeguarded Mechanical-Friction Clutch
Safeguarded press brake
 
 

 
Additional Safety Measures
Potential Hazards:
  • Operating controls should be located away from the die area and employ dual palm buttons. 

  • If a foot pedal control is used, it must be guarded. 

  • An emergency stop button should be available with easy access to the operator and a main power disconnect switch is needed.
Guarded Foot Pedal in Use Guarded foot pedal in use
  • Power transmission components are normally located away from the operator; however, hydraulic pump/motor arrangements should be enclosed. [1910.219]

  • Work area should be kept clean to prevent slipping or falling hazards.


 


 
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