Patent ID: 6246157
Filing Date: 2001-06-12
Classification: H02N

Abstract:
A linear displacement motor, comprising:a pair of shaft segments;a displacement actuator capable of expansion and contraction, said displacement actuator affixed between said shaft segments to axially move said shaft segments relative to each other when said displacement actuator expands or contracts; anda pair of clamps arranged to receive respective ones of said shaft segments, each said clamp arranged to alternately close to hold its respective shaft segment and open to allow its respective shaft segment to axially displace;wherein said displacement actuator comprises a piezoelectric body that expands when a voltage is applied and contracts when the voltage is removed, said displacement actuator further comprising a retainer for said piezoelectric body that contacts said body and retains said body in compression between said shaft segments without being bonded to said body, said retainer further comprising two thrust plates and two or more compression screws having respective screw heads, each thrust plate attached to a respective one of said shaft segments, said piezoelectric body mounted between said thrust plates opposite said shaft segments and each said compression screw engaging said thrust plates to hold said piezoelectric body under compression.