Power Presses

Power Presses

Mechanical power presses are used to shear, punch, form, or assemble metals or other materials by using tools or dies attached to slides or rams. Metalworking takes place by putting stock on a bottom die and striking it with a top die, which is attached to a crankshaft with connecting rods. Rotation of the crankshaft is accomplished from a motor, flywheel, and gear power transmission.

The two primary types of power presses, based on their clutch type, include full revolution (mechanical clutch) and part-revolution clutch. A full revolution clutch is a type of clutch that, when tripped, cannot be disengaged until the crankshaft has almost completed a full revolution and the press slides a full stroke. Power presses with this type of clutch were designed to make one full machine stroke or crankshaft revolution after each engagement of the mechanical pin, collar, or rolling key. A part revolution clutch, in contrast, can be disengaged at any point before the crankshaft has completed a full revolution and the press slide has completed a full stroke. Most power presses with part revolution clutches are air clutch and brake. After trapping air in a chamber or tube, the compressed air causes the clutch to engage and the brake is disengaged; the press then makes a single stroke.