Impact micro-positioning actuator

In an impact micro-positioning actuator having an output shaft, a nut for threadingly receiving the output shaft, and an impacting device for impacting the nut and thereby turning the nut relative to the output shaft, a mechanism for controlling slip between the nut and the shaft, comprising:

• a bearing element for frictionally engaging a selected one of (a) the output shaft and (b) the nut;
• a housing for supporting said bearing element mounted to the other of (a) and (b);
• and
• a biasing member for biasing said bearing element outwardly from said housing toward said selected one of (a) and (b), so that friction between said nut and shaft is dominant over the friction between said bearing element and said selected one of (a) and (b).

An impact micro-positioning actuator comprising:

• an elongate output shaft having a length in a first dimension parallel to the elongate axis of the shaft and a shaft diameter in a second, perpendicular dimension that is less than said length;
• a nut for threadingly receiving said output shaft;
• an impacting device for producing an impact on said nut and thereby turning said nut relative to the output shaft;
• and
• an inertial control disk having a center of rotation aligned with the axis of rotation of the shaft, said inertial control disk having a disk diameter in said first dimension and a length in said second dimension that is less than said disk diameter.