US 6,307,301 B1 · Buckling resistant piezoelectric actuator

Abstract

A piezoelectric actuator assembly allows maximization of the cross-sectional area of a piezoelectric driver assembly such that axial stiffness of the actuator assembly is substantially increased. The actuator assembly is coupled to an application structure and includes the piezoelectric driver assembly having a stack inboard end longitudinally extending in an inboard direction with respect to the application structure. The driver assembly also has a stack outboard end longitudinally extending in an outboard direction with respect to the application structure. The driver assembly further provides a longitudinal displacement in response to an applied voltage. The actuator assembly also includes an amplification arm having an arm outboard end coupled to a load. An outboard hinge mechanism rotatably couples an arm inboard end of the amplification arm to the stack outboard end such that the arm outboard end extends in the outboard direction. Voltage signals selectively applied to the driver assembly cause rotational displacement of the amplification arm.

Claims23

Dependent claims

A piezoelectric actuator assembly for displacing a load comprising:

a piezoelectric driver assembly coupled to an application structure, the driver assembly having a stack inboard end longitudinally extending in an inboard direction with respect to the application structure and a stack outboard end longitudinally extending in an outboard direction with respect to the application structure, the driver assembly having a longitudinal displacement in response to an applied voltage;
an amplification arm having an arm outboard end coupled to a load and an arm inboard end;
and
an outboard hinge mechanism rotatably coupling the arm inboard end of the amplification arm to the stack outboard end such that the arm outboard end extends in the outboard direction and both arm ends are positioned on a same side of the hinge mechanism.

1 more element

An outboard hinge mechanism for rotatably coupling an outboard end of a piezoelectric driver assembly to an amplification arm, the driver assembly having a first piezoelectric stack and a second piezoelectric stack, the hinge mechanism comprising:

an axis connection mechanism extending through the driver assembly and the amplification arm, the axis connection mechanism fixedly coupled to an application structure;
a first stack joint fixedly coupled to the first piezoelectric stack and moveably coupled to the amplification arm such that longitudinal displacement of the first piezoelectric stack in an outboard direction with respect to the application structure causes rotation of the amplification arm about the axis connection mechanism in a first output direction;
and
a second stack joint fixedly coupled to the second piezoelectric stack and moveably coupled to the amplification arm such that longitudinal displacement of the second piezoelectric stack in the outboard direction causes rotation of the amplification arm about the axis connection mechanism in a second output direction.

1 more element

A method for displacing a load, the method comprising the steps of:

longitudinally extending a stack inboard end of a piezoelectric driver assembly in an inboard direction with respect to an attached application structure;
longitudinally extending a stack outboard end of the piezoelectric driver assembly in an outboard direction with respect to the application structure;
generating longitudinal displacement of the driver assembly in response to an applied voltage;
coupling an outboard end of an amplification arm to the load;
and
rotatably coupling an arm inboard end of the amplification arm to the stack outboard end.

3 more elements

Dependencies are inferred from the claim text.

Buckling resistant piezoelectric actuator

Life of this patent

Buckling resistant piezoelectric actuator

Life of this patent

Abstract

Claims23