Apparatus for securing a ferroelectric stack to a weighted projection

Abstract

A coupling ring is bonded onto the opposite ends of a ferroelectric stack ving substantially the same thermal expansion coefficient as the stack. A thin film of silicone compound is wiped onto the axially exposed surfaces of the rings and surfaces provided in a head and a tail mass are configured to mate with them. A plurality of microspheres are mixed uniformly through a liquid adhesive and this mixture is coated onto the suitably shaped surfaces on the head and tail mass. A stress rod reaching between the head and tail mass axially compresses the ferroelectric stack and excess adhesive mixture is squeezed from between the mating surfaces. The thickness of the liquid adhesive is restricted to the diameter of the microspheres to ensure a high impedance match and upon applying the proper amount of heat, rigid joints are set up between the now hardened adhesive and the head and tail mass. Nonrigid joints are created across the silicone compound films to create an optimum impedance match between the ferroelectric stack and the masses and to prevent the transfer of self-destructive tensile strains as the head and tail masses change dimensions in response to changing ambient temperatures.