MAGNETOSTRICTIVE CLAMPING DEVICE

摘要

A magnetostrictive clamping device (149) comprising first and second arm members (152, 153) extending in respective first and second directions defining a plane. Each of the first and second arm members has opposite first and second end portions (152a, 152b, 153a, 153b). The first end portions are pivotally interconnected for permitting relative movement of the second end portions between a first position in which the second end portions are spaced apart and a second position in which the second end portions are spaced closer together. An actuator (157) is coupled to at least one of the first and second arm members for causing the relative movement of the second end portions between the first and second positions. The actuator has a drive element at least partially made from a magnetostrictive material and produces an electromagnetic field which extends through at least a portion of the drive element. The drive element is changeable between a first length when in the absence of the electromagnetic field and a second length when in the presence of the electromagnetic field. The length of the drive element extends along a line spaced apart from the plane so as to permit the drive element to be disposed alongside at least one of the first and second arm members and thereby provide a magnetostrictive clamping device of reduced length.