Wire clamp with piezoelectric actuator and method and apparatus for applying a preload force to the piezoelectric actuator

A method of applying a preload force to a piezoelectric actuator of a wire clamp, the wire clamp comprising a clamp body and a pair of arms coupled to the clamp body, the piezoelectric actuator having a longitudinal axis extending between a first end and a second end and being coupled to the pair of arms at the first end and to the clamp body at the second end;

• the method comprising the steps of:
• providing a wedge having an inclined surface;
• providing a mating inclined surface such that a gap is defined between the mating inclined surface and the piezoelectric actuator, or between the clamp body and the mating inclined surface, the wedge being slidable over the mating inclined surface;
• inserting the wedge into the gap such that the inclined surface contacts the mating inclined surface;
• and
• applying a force to the wedge in a direction transverse to the longitudinal axis of the actuator to thereby apply a preload force along the longitudinal axis.

A jig for applying a preload force to a piezoelectric actuator of a wire clamp, the wire clamp comprising:

• a clamp body and a pair of arms coupled to the clamp body, the piezoelectric actuator having a longitudinal axis extending between a first end and a second end and being coupled to the pair of arms at the first end and to the clamp body at the second end, the second end of the piezoelectric actuator being coupled to the clamp body by a preload mechanism for applying a preload force along the longitudinal axis, the preload mechanism comprising at least one wedge having an inclined surface which is slidable over a mating inclined surface;
• the jig comprising:
• a clamp support having a recess to receive the clamp body;
• a tensioning platform extending from the clamp support and being elevated relative to the recess, the tensioning platform having a threaded bore which, when the clamp body is received in the clamp support, is aligned with the at least one wedge;
• and
• a tensioning screw receivable in the threaded bore such that a tip of the tensioning screw contacts the at least one wedge, and such that tightening of the tensioning screw applies a force to the at least one wedge in a direction transverse to the longitudinal axis of the piezoelectric element.