Inventors:
Patricia L. Williams - Rochester NY
Assignee:
Eastman Kodak Company - Rochester NY
International Classification:
H02N 1000
Abstract:
A stepper motor includes the following. A rotatable hub. A first shaped memory alloy (abbreviated to SMA) rotary-driver, which when heated undergoes a shape change to rotationally couple with the hub and rotate the hub in a predetermined direction, and which can be deformed to reverse the shape change to rotationally uncouple from the hub. A first return spring connected with the first SMA rotary-driver for deforming the first SMA rotary-driver, when no longer heated, to reverse the shape change of the first SMA rotary-driver and rotationally uncouple the first SMA rotary driver from the hub. A second SMA rotary-driver, which when heated undergoes a shape change to rotationally couple with the hub and rotate the hub in the predetermined direction, and which when can be deformed to reverse the shape change to rotationally uncouple from the hub. A second return spring connected with the second SMA rotary-driver for deforming the second SMA rotary-driver, when no longer heated, to reverse the shape change of the second SMA rotary-driver and rotationally uncouple the second SMA rotary-driver from the hub. A control device for heating the first and second SMA rotary-drivers in succession and only one at a time.