Piezoelectric step-motion actuator

A step-motion actuator comprising:

• a plurality of teeth;
• a piezoelectric element adapted to convert electric energy to kinetic energy;
• a compression frame secured about the piezoelectric element and adapted to pre-compress the piezoelectric element so as to reduce tensile loads thereon;
• a mass secured to an arm, wherein the mass is spring-biased toward the compression frame and the piezoelectric element such that the piezoelectric element converts electrical energy into kinetic energy in the form of movement of the mass and the arm;
• a movable drive pawl coupled with the arm and positioned so as to engage one or more of the teeth in a forward direction, wherein movement of the mass and the arm causes movement of the drive pawl, and wherein the drive pawl drives against the one or more teeth to accomplish a step-motion in the forward direction;
• and
• a movable hold pawl positioned so as to engage one or more of the teeth in a reverse direction during movement of the drive pawl.

A step-motion actuator comprising:

• a plurality of teeth;
• a piezoelectric element adapted to convert electric energy to kinetic energy;
• a compression frame secured about the piezoelectric element and adapted to pre-compress the piezoelectric element so as to reduce tensile loads thereon;
• a first mass spring-biased toward a first end of the compression frame and the piezoelectric element;
• a second mass spring-biased toward a second end of the compression frame and the piezoelectric element, wherein the piezoelectric element converts electrical energy into kinetic energy in the form of movement of the first mass and the second mass in substantially different directions;
• a movable drive pawl coupled with the first mass and the second mass and positioned so as to engage one or more of the teeth in a forward direction, wherein movement of the first mass and the second mass causes movement of the drive pawl, and wherein the drive pawl drives against the one or more teeth to accomplish a step-motion in the forward direction;
• and
• a movable hold pawl positioned so as to engage one or more of the teeth in a reverse direction during movement of the drive pawl.

A step-motion actuator comprising:

• a plurality of teeth;
• a piezoelectric element adapted to convert electric energy to kinetic energy;
• a compression frame secured about the piezoelectric element and adapted to pre-compress the piezoelectric element so as to reduce tensile loads thereon, wherein the piezoelectric element and compression frame are movable;
• an arm spring-biased directly against the compression frame such that the piezoelectric element converts electrical energy into kinetic energy in the form of movement of the piezoelectric element and compression frame against the arm and thereby moves the arm;
• a movable drive pawl coupled with the arm and positioned so as to engage one or more of the teeth in a forward direction, wherein movement of the arm causes movement of the drive pawl, and wherein the drive pawl drives against the one or more teeth to accomplish a step-motion in the forward direction;
• and
• a movable hold pawl positioned so as to engage one or more of the teeth in a reverse direction during movement of the drive pawl.