Basically, the cushions are sets of pneumatic or hydraulic cylinders which provide an adjustable pressing force and ejection. They are mainly used in stamping operations.
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Types of cushions depending on the position in the press:
Upper cushions
They are usually of limited force, stroke and size and are housed inside the slide. Their use tends to be in decline.
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Lower cushions
Located below the press table and can be fixed or moveable. They can be used with their own guide system but when off-centre forces are to be used it is better to provide an additional guide system.
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Types of cushions depending on their actuation:
Standard cushion
Triggered by the press slide in either downward or upward movement, always exercising the set force.
Cushion with retention device
It accompanies the down stroke of the slide with the force set. When it reaches bottom dead centre, it locks the cushion until a set position of the upward movement of the slide is reached. Then, cushion rising is permitted.
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Hydraulic cushion with independent movement
The main function of these cushions is to permit a complete control of the force and position. This full control of the cushion force helps to avoid the formation of wrinkles, and guarantee an optimal material flow during the forming operation.
Position control makes possible to work with different cushion strokes without need of changing the pins, to adjust upstroke velocity, to work as an ejector independent of the slide.
The cushion makes a pre-acceleration in order to reach a percentage of slide speed at the moment of impact. . It improves lifetime of dies, the quality of parts and reduces noise during the work.
All actuations are programmable as a die data.
Nominal forces
We manufacture cushions from 60 kN to 6,000 kN. of nominal force.
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