Importance

Loading Importance Indicators...

Abstract

To provide the necessary vertical motion of a wire- bonding head (20) mounted on a flexural pivot (16), a wire-bonding machine (10) includes an actuator comprising a permanent magnet (56) mounted on the flexural pivot (16) and extending into the central passage (49) of a ferromagnetic sleeve (46) in which two oppositely wound coils (50 and 52) are mounted. The magnetic force resulting from current flow through the coils (50 and 52) causes the head assembly (18) to pivot about the flexural-pivot axis (16) and thus cause the magnet (56) to move out of symmetry with respect to the ferromagnetic sleeve (46). The resultant attraction between the permanent magnet (56) and the ferromagnetic sleeve (46) tends to counteract the resistance of the flexural pivot (16) to pivotal displacement from a rest position but does not additionally reduce the stiffness of the flexural pivot to other, undesired modes of motion.

Loading the Abstract Image...

First Claim