TY - GEN

T1 - Electromagnetic dampening of the cutting shock on sheet metal presses

AU - Behrens, B. A.

AU - Marthiens, O.

AU - Werbs, M.

PY - 2005

Y1 - 2005

N2 - The cutting shock within the stamping process causes an oscillation of the ram and the upper tool of a mechanical stamping press. This oscillation consists of a transversal stroke oscillation and rotary tilting oscillation. The tilting oscillation is caused by a noncentric cutting force in the tool. The oscillation of the ram results in a frictional movement between the upper tool and the lower die and respectively the cutting material. This frictional movement can be reduced by damping the oscillation. Therefore an electromagnetic damper is being developed at the Institute of Metal Forming and Metal Forming Machine Tools. The damper is based on the physical principle of the Lorentz Force which involves the deceleration of a moving closed loop electrical conductor circuit in a magnetic field. The deceleration force increases with the intensity of the magnetic field and with increasing velocity of the conductor. The electromagnetic damper consists of two parts. The upper part (actor) is attached to the ram and contains a short-circuited coil. The lower part (stator) is situated on the bolster plate and consists of a pile of permanent magnets. The intensity of the magnetic field depends on the material of the permanent magnets and on the size of the air gap between the upper and the lower part of the damper. The damping force of the electromagnetic damper increases with the conductivity of the short-circuited coil, the intensity of the magnetic field and with the relative velocity between the actor and stator. The latter equals the ram velocity. The movement of the ram after the cutting shock is primarily determined by the characteristics of the press and of the cutting process. The electromagnetic damper lowers the ram oscillations and thereby reduces the tool wear.

AB - The cutting shock within the stamping process causes an oscillation of the ram and the upper tool of a mechanical stamping press. This oscillation consists of a transversal stroke oscillation and rotary tilting oscillation. The tilting oscillation is caused by a noncentric cutting force in the tool. The oscillation of the ram results in a frictional movement between the upper tool and the lower die and respectively the cutting material. This frictional movement can be reduced by damping the oscillation. Therefore an electromagnetic damper is being developed at the Institute of Metal Forming and Metal Forming Machine Tools. The damper is based on the physical principle of the Lorentz Force which involves the deceleration of a moving closed loop electrical conductor circuit in a magnetic field. The deceleration force increases with the intensity of the magnetic field and with increasing velocity of the conductor. The electromagnetic damper consists of two parts. The upper part (actor) is attached to the ram and contains a short-circuited coil. The lower part (stator) is situated on the bolster plate and consists of a pile of permanent magnets. The intensity of the magnetic field depends on the material of the permanent magnets and on the size of the air gap between the upper and the lower part of the damper. The damping force of the electromagnetic damper increases with the conductivity of the short-circuited coil, the intensity of the magnetic field and with the relative velocity between the actor and stator. The latter equals the ram velocity. The movement of the ram after the cutting shock is primarily determined by the characteristics of the press and of the cutting process. The electromagnetic damper lowers the ram oscillations and thereby reduces the tool wear.

KW - Cutting shock

KW - Damping

UR - http://www.scopus.com/inward/record.url?scp=84899659111&partnerID=8YFLogxK

M3 - Conference contribution

AN - SCOPUS:84899659111

SN - 888733174X

BT - Advanced technology of plasticity 2005

CY - Padova

T2 - 8th International Conference on Technology of Plasticity, ICTP 2005

Y2 - 9 October 2005 through 13 October 2005

ER -